FILE PHOTO: U.S. Secretary of State Mike Pompeo speaks at a press conference at the Ministerial to Advance Religious Freedom at the State Department in Washington, U.S., July 26, 2018. REUTERS/Alex Wroblewski

WASHINGTON (Reuters) - U.S. Secretary of State Mike Pompeo will not meet with his Iranian counterpart during a meeting of southeast Asian nations in Singapore this weekend, a senior State Department official said on Tuesday, a day after U.S. President Donald Trump offered talks with Tehran without preconditions.

“Iran is not a member of any of the multilateral gatherings so there are no plans for any engagement with Iran,” the senior official told reporters to preview Pompeo’s visit this week to Singapore, Indonesia and Malaysia.

“Related issues, of course - terrorism and proliferation, will be discussed at several of these meetings,” the official added, referring to U.S. charges that Tehran supports extremist groups in the Middle East.

Both Pompeo and Iranian Foreign Minister Mohammad Javad Zarif will attend Saturday’s meeting of the 10-nation Association of Southeast Asian Nations bloc (ASEAN).

Trump said on Monday he would be willing to meet with Iranian President Hassan Rouhani to discuss ways to improve ties, months after he pulled the United States out of the 2015 Iran nuclear deal in May.

Later, the White House clarified that Trump’s potential willingness to meet with his Iranian counterpart did not change his administration’s intent to ratchet up sanctions and rhetoric against Tehran with the stated goal of “seeking changes in the Iranian government’s behavior.”

Iranian officials rejected Trump’s offer of talks saying they saw no value in talking to the United States after it pulled out of the nuclear deal agreed between Tehran and six major powers.

Pompeo has called for broad support to pressure Iran to change its behavior.