London (CNN) -- Australia will follow the European Union's lead in imposing sanctions on Iran's oil imports, Foreign Secretary Kevin Rudd said Tuesday in London, amid international concern over Tehran's nuclear ambitions.
The European Union announced Monday it would cut off oil imports from Iran and freeze assets in an effort to starve the country's nuclear program of funding.
Rudd, speaking after a meeting of British and Australian foreign and defense officials, said Australia was "deeply concerned" about Iran and would impose parallel measures to those announced in Brussels.
"We believe this is the right course of action," he said. "We believe that for the simple reason that the Iranian nuclear weapons program is fundamentally destabilizing, not just for the wider Middle East and the Gulf states, but also for the wider world."
The sanctions announced Monday freeze the assets of Iran's central bank in European Union nations and ban the importation of Iranian oil to those countries. The measures also block European Union countries from exporting petrochemical equipment and technology to Iran, or trading diamonds and precious metals with the Middle Eastern state.
Iran says its nuclear program is not military, but the United States and many of its allies suspect Iran intends to produce a bomb. The United Nations' nuclear watchdog, the International Atomic Energy Agency, has expressed similar concerns.
British Foreign Secretary William Hague, speaking alongside Rudd, said the measures represented "a significant increase -- a major increase -- in the peaceful, legitimate pressure on the Iranian government to return to negotiations over its nuclear program.
"Until it does so, the pressure will only increase and Britain and Australia share the same sense of resolve about that," Hague added.
Rudd said the reason for such concerted action was clear.
"The message needs to be delivered to the people of Iran, the wider political elites of Iran, as well as the government of Iran, that their behavior is globally unacceptable," he said.
Tehran has threatened to close the Strait of Hormuz, the only outlet to and from the Persian Gulf, in response to sanctions -- a move that has increased international tensions. Seventeen million barrels of oil per day passed through the critical shipping lane in 2011, according to the Energy Information Administration.
Defence Secretary Philip Hammond said Tuesday that Britain had sent the British warship HMS Argyll through the strait alongside U.S. and French ships Sunday "to send a clear signal about the resolve of the international community to defend the right of free passage through international waters."
Britain also has vessels in the Gulf equipped to counter the laying of mines, he said, as part of the allied presence in the area.
"The United Kingdom has a contingent capability to reinforce that presence, should at any time it be considered necessary to do so," he warned.
Later Tuesday, Hague told lawmakers in the House of Commons that Iran would be the biggest loser if it followed through on its threat to close the Strait of Hormuz, since 95% of its own oil exports pass through it.
Hague said the passage of HMS Argyll through the strait had been a routine movement but reflected the "unwavering international commitment" to keeping it open.
"Any attempt by Iran to block the Strait would be both illegal and unsuccessful," he said, adding that the point of the sanctions was to bring Iran back to the negotiating table.
Iran's deputy foreign minister, Abbas Aragchi, said Monday that the measures against it would only harm the fragile economies of the European Union, according to the official Islamic Republic News Agency.
"Sanctions have proved ineffective in the past and will prove futile in the future, too," IRNA quoted Aragchi as saying.
Iran exports 2.2. million barrels of oil a day, with about 18% bound for European markets, according to the U.S. Energy Information Administration. The Iranian government gets about half its revenue from oil exports, according to the agency.
The world consumes about 89 million barrels of oil per day.
Rudd said Australian imports of Iranian oil were currently "negligible," while his country's exports to Iran had already declined greatly in recent years in line with foreign policy concerns. "This costs, but is a cost worth paying," he said.
Analysts have said that while the new sanctions are the toughest ever imposed, they still contain many loopholes.
Iran is expected to still be able to sell its oil to places like China, India or other Asian countries, but perhaps at a discount of 10% to 15%. About 35% of Iran's oil exports currently go to China and India.
The European Union will allow contracts that are already in place to be fulfilled until July 1, it said.
The U.S. government took its own punitive action regarding Iran Monday, with the Treasury Department targeting the nation's third-largest bank, the state-owned Bank Tejarat, for allegedly working with other Iranian banks and firms subject to sanctions tied to Iran's nuclear program.
CNN's Richard Allen Greene contributed to this report.