UK security adviser was not part of final US-Iran talks, says Starmer's spokesperson

LONDON, March 18 (Reuters) - Britain's national security adviser, Jonathan Powell, was not part of final talks between the United States and Iran before the U.S. and Israel launched strikes against Tehran, a spokesperson for Prime Minister Keir Starmer said on Wednesday.

Britain's Guardian newspaper reported on Tuesday that Powell had attended the talks and judged the offer made by Tehran on its nuclear programme significant enough to prevent a rush to war.

"These negotiations were bilateral between the U.S. and Iran, facilitated by Oman. Jonathan was not present in the talks in Geneva and was not part of talks in the residence," the spokesperson told reporters, after being asked about the report which said Powell was present in the building at Oman's ambassadorial residence in Geneva.

"No team of British officials participated in the negotiations. The UK supported the approach Steve Witkoff and Jared Kushner took and their efforts in pursuit of a negotiated solution," the spokesperson said, referring to the two White House envoys.

The United States and Israel launched attacks on Iran on February 28, sparking a conflict that has spread across the Middle East, killing thousands in the region and 13 U.S. service members.

(Reporting by Andrew MacAskill, writing by Elizabeth Piper; Editing by Kate Holton)