JERUSALEM — Sounding his toughest message on peace since being sworn in as prime minister last week, Shimon Peres warned that the process would be halted if the Palestinian leadership did not abolish the portions of the Palestinian Covenant that call for the destruction of Israel.

Peres, who has recently been wooing the support of right-wing religious parties, adopted the stance Monday at an appearance before the Knesset's Foreign Affairs and Defense Committee.

The warning came as 25 Palestinian police officers arrived in Tulkarm, the second West Bank town to be transferred to the Palestinians under the terms of the recently signed agreement for extending Palestinian autonomy in the West Bank.

Peres told the committee that Israel would keep all of its commitments in the Interim Agreement, but that the Palestinians had to keep theirs as well.

Under the terms of that agreement, signed Sept. 28 in Washington, the Palestinians promised to amend the pertinent clauses in the covenant within two months after the inauguration of the Palestinian Council.

Elections for the council are scheduled for late January.

Prior to Sept. 28, Arafat had pledged on more than one occasion to revoke the offending clauses in the Palestinian Covenant, which spells out the Palestine Liberation Organization's political agenda.

PLO leader Yasser Arafat "has to change those items in the Palestinian Covenant that call for the destruction of Israel," Peres told reporters after addressing the committee.

"This is part and parcel of the agreement. If they will not respect it, there will not be a continuation of the agreement."

Peres did not mention a deadline for his demand. He added that negotiations for a permanent-status agreement with the Palestinians would begin as scheduled in May.

Peres also said that former U.S. President Jimmy Carter and former British Prime Minister Margaret Thatcher would lead the 1,000-member international observer team that will monitor the Palestinian elections.