DUBAI, United Arab Emirates (AP) — Iran and the United States began a fourth round of negotiations Sunday over Tehran’s rapidly advancing nuclear program, officials said, just ahead of a visit by President Donald Trump to the Middle East this week.

The latest round of high stakes nuclear talks between Iran and the US have ended, with Tehran calling them difficult but with both sides agreeing to further negotiations.

By Parisa Hafezi DUBAI (Reuters) -Fresh talks between Iranian and U.S. negotiators to resolve disputes over Tehran's nuclear programme ended in Oman on Sunday with further negotiations planned, officials said,