RAMALLAH, West Bank (AP) — A senior PLO official says President Barack Obama has warned Mahmoud Abbas in a letter that U.S.-Palestinian relations might suffer if the Palestinian leader refuses to resume direct peace talks with Israel.

The White House has been pushing Abbas hard in recent days to move quickly to face-to-face negotiations, but had no comment Saturday.

The PLO official says Obama sent the letter July 16 — the strongest U.S. warning to Abbas yet.

Abbas insists he will only negotiate once Israel commits to the idea of a Palestinian state in the West Bank, Gaza and east Jerusalem. Israel's prime minister refuses to be pinned down ahead of talks.

The official spoke on condition of anonymity because the letter has not been made public.