The Vatican signed its first official treaty with the now legally recognized "State of Palestine" on Friday.

It's the first time the Vatican has officially recognized Palestinian statehood, though the Holy See welcomed a 2012 U.N. Generally Assembly decision to recognize a Palestinian state and had treated it with de facto recognition since.

Archbishop Paul Gallagher, the Vatican's foreign minister, said he hopes the Vatican's official recognition "may in some way be a stimulus to bringing a definitive end to the long-standing Israeli-Palestinian conflict, which continues to cause suffering for both parties," the Associated Press reported.

Gallagher called for Israel and Palestine to resume direct peace negotiations to work towards a two-state solution. "This certainly requires courageous decisions, but it will also offer a major contribution to peace and stability in the region," he said, according to Reuters.

The treaty is a result of 15 years of discussions and was signed by Gallagher and his Palestinian counterpart, Riad al-Malki, at a ceremony inside the Vatican on Friday. It concerns the activities of the Church in areas of the Holy Land controlled by the Palestinian Authority.

Al-Malki said he hopes the treaty will help "recognition of the right of the Palestinian people to self-determination, freedom and dignity in an independent state of their own, free from the shackles of occupation," according to Reuters. The treaty would "not have been possible without the blessing of his Holiness Pop Francis for our efforts to reach it," he added, Al Jazeera reported.

Israel's Foreign Ministry expressed regret over the decision. "This hasty step damages the prospects for advancing a peace agreement, and harms the international effort to convince the Palestinian Authority to return to direct negotiations with Israel," Emmanuel Nahshon, a spokesman for Israeli foreign ministry, said, according to the Times of Israel.

As of last year, 135 of the 193 U.N. member states officially recognized the State of Palestine, while 160 of the U.N.'s member states recognize Israel.

In October, Sweden became the first major European country to acknowledge Palestine. The European Union, however, like the U.S., believes that independent recognition can only come from negotiations with Israel.