- Palestinian president, Pope Francis meet at Vatican
- Palestinians open state embassy in Vatican City
"We are very grateful about the role that the Holy See has played for a just and lasting peace in the Holy Land, and for having opened an embassy of Palestine in the Vatican for first time," Abbas said, according to the official Palestinian news agency WAFA
"We are proud to be the birthplace of Christianity and about having one of the oldest Christian communities in the world."
Issa Kassissieh, the Palestinian ambassador to the Holy See, called the move "a significant achievement for the Palestinian people," WAFA said.
Israel has yet to respond to news of the opening.
Many other countries, including Israel, have embassies in Vatican City.
Vatican policy has long held that a two-state solution is the best road to peace in the Holy Land, and Francis has taken steps to raise the profile of a Palestinian state.
The Vatican had referred to Palestine as a state since November 2012, when the United Nations voted to recognize it as a nonmember observer state.
Francis broke ground by formally recognizing Palestinian statehood
in a legal document in May 2015.
Also in 2015, Francis declared nuns Marie Alphonsine Ghattas and Mariam Baouardy the first two Palestinian saints of modern times.
In June 2014, Francis hosted Abbas and late Israeli President Shimon Peres for an unprecedented prayer ceremony at the Vatican.
The UN General Assembly adopted a resolution In September 2015
allowing the "State of Palestine" and the Vatican to raise their flags outside of UN headquarters and UN offices.
At the Vatican on Saturday, Abbas said he planned to attend a conference the following day in Paris to explore ways to restart the Israeli-Palestinian peace process.
US Secretary of State John Kerry is among officials from more than 70 nations who plan to attend the conference. Israel has said it will not participate.