U.S. Middle East peace envoy George Mitchell, who has led the Obama administration's effort to restart direct negotiations between Israel and the Palestinians, plans to resign on Friday, Reuters quoted a U.S. official as saying. Mitchell's departure comes ahead of U.S. President Barack Obama's expected speech laying out his new Middle East strategy. The official, speaking on condition of anonymity, said Mitchell's resignation would be announced by the White House later on Friday. Mitchell, 77, a former U.S. senator who helped broker the Northern Ireland peace deal, was one of the first members of Obama's foreign policy team to be announced and has shuttled extensively between Washington and Middle East capitals trying to set up new negotiations. Faced with a deadlock, the United States in December scrapped efforts to relaunch direct peace talks and Mitchell has not visited the region since then.