February 24, 2023 - It's now one year since Russia's invasion of Ukraine began

On Friday, the Russian foreign ministry issued a statement warning NATO and Ukraine against "adventurous steps" in Transnistria — a breakaway region of Moldova where some 1,500 Russian troops are stationed.

It warned that while Moscow stands for using "political and diplomatic means" to solve any issues, Russian forces will ensure the "protection of their compatriots" in Colbasna in Transnistria, and will "adequately respond" to any provocations from Kyiv.

"Any action that poses a threat to their security will be considered, in accordance with international law, as an attack on the Russian Federation," the statement added.

Ukrainian officials have recently accused Russia of plotting to destabilize Moldova. On February 13, Moldova's President Maia Sandu echoed Ukraine's claims and accused Russia of planning to use "saboteurs who have undergone military training and are disguised as civilians" to destabilize the country.

"The statements of President Zelensky about the plans of the Russian Federation to destabilize the Republic of Moldova have been confirmed by our institutions," she said.

Late Thursday, the Russian defense ministry claimed that Kyiv had "intensified efforts to prepare for an invasion of the Transnistrian Moldovan Republic."

A prominent Russian military blogger, who goes by the name of WarGonzo, said that "given that we have no direct land supply to Transnistria, and that the unfriendly Moldovan government will most certainly not allow our air force into the sky, the Russian garrison in Transnistria is now probably in the most vulnerable position, compared to the position on other fronts."

Ukraine responds: Addressing Russian accusations that it is building up forces close to the Moldovan territory, a Ukrainian State Border Service spokesperson said the Ukrainian military and National Guard have taken “increased measures on the border with Transnistria" but solely "to prevent any provocations from the other side.”

"Ukraine has always paid attention to Transnistria, as it is actually an enclave of Russia, which could have been used against our state as early as February 24 last year,” said the spokesperson, Andrii Demchenko.

“Fortunately, we did not record any active or provocative actions in this direction either," Demchenko added.

CNN's Mariya Knight contributed to this report.

Germany will send a further four Leopard 2 tanks to Ukraine, the German defense ministry said in a statement Friday.

This increases the number of tanks Germany is sending to Ukraine from 14 to 18.

“Defense Minister Boris Pistorius, consulting with his military advisors, today decided to hand over a further four Leopard 2 A6 main battle tanks from Bundeswehr stocks to Ukraine,” the statement said.

“With this decision, together with our Portuguese and Swedish partners, we are now able to provide a mixed Ukrainian battalion,” the statement added.

“Together with Poland, an initiative was launched to provide Ukraine with two battalions of Leopard 2 main battle tanks. While Poland has taken over the share of supplying Leopard 2 A4, Germany is coordinating the Leopard 2 A6 share,” the German defense ministry said.

“With today's announcement by Sweden to deliver ten Leopard 2 A5 main battle tanks, which are technically similar to the German 2 A6 version, together with Portugal we are able to make 31 Leopard 2 available to Ukraine,” the statement added.

Russia's war in Ukraine needs NATO countries to act together, including the United States, because the war may be in Europe right now, but it could become a direct threat to the US, Polish Consul General Adrian Kubicki said Tuesday.

Russia's imperialistic ambitions are not new — the threat started with Moscow's invasion of Crimea, Kubicki explained, adding that there have always been concerns that Russian President Vladimir Putin would not stop at Crimea or even Ukraine.

"We learned from Crimea, and we acted jointly this time," he said. "Putin decided to invade to prove that (the) West is at its weakest given our internal discussions, but we have proved he is wrong."

So far, US officials have made clear that American troops won’t engage directly with Russian forces, and NATO members have also been cautious about its support measures for Ukraine so as to not engage in a “full-fledged war in Europe.”

Kubicki reiterated that a unified response is imperative because if concerns about Putin's ambition prove true and the war spills into a NATO member nation, it would trigger Article 5 of the alliance.

Article 5 is the principle that an attack on one member of NATO is an attack on all members. It’s been a cornerstone of the 30-member alliance since it was founded in 1949 as a counterweight to the Soviet Union.

Warning Putin against escalation is necessary because the stakes are high and Russian forces are "literally on the border" of Poland, Kubicki noted.

"We need to join our forces to help Ukrainians defend themselves, and also to also defend us," he said. "This war is not very distant [for Americans,]" he added, saying it may "easily ... become a global conflict. It might actually pose a direct threat to the United States of America."

Russia bears responsibility for the harm and suffering to not only the people of Ukraine, but to the global economy caused by the war, US Treasury Secretary Janet Yellen told MSNBC.

This comes following her remarks directly to Russian officials at the G20 meeting this week in India.

"I think there’s widespread agreement that ending this brutal war on Ukraine is the single most-important policy change that would benefit the global economy and its outlook," she said, adding that the "worst damage" falls on "very low income countries that are seeing food prices and energy prices rise” as a result of the war.

Discussing US sanctions imposed on Russia, she said she believes they are having a significant impact even as authorities look for ways to strengthen them and diminish ways for Russia to evade the sanctions. The objective is to degrade Russia's ability to continue the war, she added.

Sweden has pledged to send Leopard 2 tanks to Ukraine, Swedish Prime Minister Ulf Kristersson said Friday.

The military package also includes further air defense components, Kristersson said in a tweet.

Landmarks around the world — Eiffel Tower, Sydney Opera House, Empire State Building and others — lit up in the colors of the Ukrainian flag to mark the one-year anniversary of Russia's full-scale invasion of the country.

Take a look:

France: Eiffel Tower

Australia: Sydney Opera House

Belgium: European Union buildings

United States of America: Empire State Building

The Biden administration has announced additional sanctions against Russia as well as additional support for Ukraine on the one-year anniversary of the invasion.

Support for Ukraine includes $9.9 billion in grant financing "to help Ukraine meet the critical needs of its citizens, including healthcare, education, and emergency services."

The White House also announced sanctions for "over 200 individuals and entities, including both Russian and third-country actors across Europe, Asia, and the Middle East that are supporting Russia’s war effort."

The US Treasury Department on Friday said it took “one of its most significant sanctions actions to date” to crack down on those aiding Moscow’s war against Ukraine, targeting Russia’s metals and mining sector, its financial institutions, its military supply chain, and individuals and companies worldwide that are helping Moscow avoid existing sanctions. 

Friday’s sweeping actions are meant fill in gaps in existing sanctions that have been imposed over the past year of the war and are intended to impair “key revenue generating sectors in order to further degrade Russia’s economy and diminish its ability to wage war against Ukraine,” according to a White House fact sheet.

The latest tranche of Treasury Department sanctions target a total of 22 individuals and 83 entities, according to a news release, and they were taken in coordination with the Group of Seven, an organization of leaders from some of the world’s largest economies: Canada, France, Germany, Italy, Japan, the United Kingdom and the US.

In addition to the sanctions, the US Commerce Department on Friday “will take several export control actions, listing nearly 90 Russian and third country companies, including in China among other countries, on the Entity List for engaging in sanction evasion and backfill activities in support of Russia’s defense sector,” the fact sheet said. 

Friday’s Treasury sanctions specifically target individuals and companies based outside of Russia that are connected to sanctions evasion, “including those related to arms trafficking and illicit finance,” the Treasury news release said.

In a statement shared by the British Embassy in Moscow, UK Foreign Secretary James Cleverly urged Russia to withdraw its forces from Ukraine and enter negotiations in good faith.

Cleverly also addressed the Russian people.

“The people of Ukraine do not want war. The rest of the world does not want war. Nor, I believe, do you,” he said. “This war is senseless. It is tragic. The Russian State has fabricated pretext after pretext to justify it.”

Marking the first anniversary of the Russia’s war on Ukraine, Cleverly said, “Thousands of your sons, brothers and loved-ones have been killed. Prices are rising, incomes are falling, and Russia is becoming ever more dependent on foreign powers.”

The UK has “no quarrel with the Russian people” but only with “the path your government is taking,” Cleverly added, saying a “brighter future is possible, but emphasized that the Russian State must change course.”

“There is no going back to the situation before February 24. There is no return to business as usual with Russia!”

Polish President Andrzej Duda marked the one-year anniversary of the Russian invasion of Ukraine by pledging not to return to ordinary relations with Moscow in the future.

Duda recalled what Ukrainian President Volodymyr Zelensky said to him on February 23, 2022 – on the eve of the invasion. 

He said Poland knew Ukraine "would not fall within a week" as initially expected, because of the freedom that unites both countries. 

Duda praised the generosity of Polish families, who have helped provide shelter to millions of Ukrainian refugees who fled to the country since the war began. “There were and there are no refugee camps in Poland. We welcomed and continue to welcome our guests in our homes." 

The President also acknowledged the importance of American support. “All this would not have been possible without the strong leadership of the United States," Duda said, adding that the US "is the guarantee of security on the old continent.”