The Palestinian president says he is optimistic that U.S. Secretary of State John Kerry will succeed in restarting peace talks between Israel and the Palestinians.

Mahmoud Abbas delivered the upbeat assessment on Tuesday, two days after Kerry ended his latest peace mission to the region without any breakthroughs.

At a news conference with the Italian foreign minister, Abbas said Kerry presented "useful and constructive suggestions." He says the Palestinians are optimistic because Kerry is "serious and determined to reach a solution."

Kerry has been working for months on finding a formula to restart peace talks, which have been stalled for nearly five years. Before leaving Sunday, Kerry said he had significantly narrowed the gaps between the sides and promised to return to the region soon.