U.S. Secretary of State John Kerry will meet Palestinian president Mahmud Abbas in Istanbul on Sunday, the State Department said, as a US-led peace push focusing on the Palestinian economy steps up.

Kerry and Abbas, who have met several times recently, will "continue the conversation that they've been having for several weeks now about how to get both sides back to the table," a State Department official said.

Kerry warned Wednesday that time was slipping away to reach a peace deal between Israel and the Palestinians, stressing for the first time that there may only be a year or two left.

The top US diplomat is working on a plan to try to boost the Palestinian economy as part of efforts to restore trust between the two sides. The plan will be discussed in the talks with Abbas, the State Department official said.

Abbas was visiting Turkey on Saturday and Sunday for talks with top officials including Prime Minister Recep Tayyip Erdogan, who has sparked concern by announcing his intention to visit the Hamas-ruled Gaza Strip next month, after a trip to the United States.

Abbas's West Bank-based nationalist Fatah movement, a long-time rival to the Islamist Hamas, has criticised Erdogan's Gaza trip as fostering intra-Palestinian divisions.

Kerry, in Istanbul on Saturday for a meeting of core members of the "Friends of Syria" group backing the Syrian opposition, was also due to meet Erdogan on Sunday.