UNITED NATIONS (AP) — The Palestinian ambassador to the United Nations said Wednesday his government may seek to join the International Criminal Court and more U.N. agencies if there is no progress in peace talks with the Israelis.

Riyad Mansour told a news conference that the 15 international conventions the Palestinians are seeking to join is just a first group, and more could follow depending on Israel's actions.

"The leadership will observe and see how things unfold, and it will decide accordingly the timing of the second batch and the third batch and so on and so forth, on the basis of the interests of the Palestinian people," he said.

In a surprise move, Palestinian President Mahmoud Abbas on Tuesday resumed a campaign for further international recognition of a state of Palestine, signing applications for the Palestinians to join 15 international treaties and conventions. The Palestinians had promised to suspend such efforts during nine months of peace negotiations with Israel that end on April 29.

Mansour insisted that the Palestinians hadn't broken any agreement, saying Israel had failed to carry out a promised release of Palestinian prisoners by the end of March.

"We are exercising our legal right as a state to join these instruments," he said. "We consider the action by our president as a step to consolidate and strengthen the pillars of the state of Palestine in the international system."

Mansour said the Palestinians remain willing and ready to engage in political talks leading to a two-state solution and independence.

"We are not looking for a confrontation or fight with anyone. We are exercising our rights, and we will not be apologetic about exercising our rights," Mansour said.

When the U.N. General Assembly recognized a state of Palestine in the West Bank, Gaza and east Jerusalem in October 2012, the Palestinians gained the right to seek membership in U.N. institutions and treaty bodies and possibly take their complaints over Israeli settlement-building on occupied land to the International Criminal Court, which is independent.

Palestine joined the Paris-based UNESCO in 2011, leading to a U.S. cutoff of funding under a U.S. law that bans support for any U.N. agency with Palestine as a member.

The Palestinians have held off joining the ICC and more U.N. agencies, which could face similar funding crises, during negotiations with Israel.

Palestinian officials earlier Wednesday handed letters for accession to 13 international conventions and treaties to Robert Serry, the U.N. special coordinator for the Middle East peace process, who is expected to deliver the originals to Secretary-General Ban Ki-moon on Thursday, U.N. deputy spokesman Farhan Haq said.

They include the Vienna Convention on Diplomatic Relations, the Convention on the Rights of the Child, the Convention on the Elimination of All Forms of Discrimination Against Women, the International Covenant on Civil and Political Rights, the International Covenant on Economic, Social and Cultural Rights and conventions against torture, corruption and the prevention of genocide.

Mansour said he expects the U.N.'s legal department to review the applications and determine within 30 days that Palestine can be a state party to the 13 conventions.

The Palestinian officials also delivered a letter asking to become a party to the Geneva Conventions to a Swiss representative, and a letter to join The Hague Convention (IV) respecting the Laws and Customs of War on Land to a representative of the Netherlands.

Mansour said the Palestinians have "a unique situation" related to the Fourth Geneva Convention and the First Additional Protocol, which establish the ground rules for what is considered humane during wartime.

Since Palestinian land is under occupation, he said, the state of Palestine will immediately become a party to the convention.

Mansour said the Palestinians can then call for meetings of state parties to the convention without getting a General Assembly resolution if Israel isn't honoring its obligations under the convention and demand enforcement.