PARK CITY, Utah — Republican Mitt Romney criticized President Barack Obama’s handling of foreign policy, telling financial backers at his annual conference Friday that everything the nation fought for during the lengthy Iraq war could vanish.

The 2012 Republican presidential nominee said at the start of his annual ideas summit at a luxurious Utah resort that the foreign policy agenda pushed by Obama, his former rival, Vice President Joe Biden and former Secretary of State Hillary Clinton has been a “monumental bust.”

“Tragically, all we’ve fought for in Iraq, all that 4,500 American lives were shed to gain, is on the cusp, potentially, of vanishing,” Romney said.

Romney added his voice to a number of Republicans who have accused Obama of being slow to respond in Iraq following the capture of two cities by an al Qaeda-inspired militant group and concerns it could push toward Baghdad. He spoke shortly before Obama told reporters from the South Lawn that he was weighing a range of options to halt the violent Islamic insurgency.

In his 15-minute address to about 300 former campaign donors and supporters, Romney pointed to a number of global hot spots, noting that Syria is in its third year of civil war, North Korea has carried out nuclear missile tests and Russia has captured Crimea.

The conference is expected to include speeches by a number of potential 2016 Republican presidential candidates, including Wisconsin Rep. Paul Ryan, Romney’s running mate; New Jersey Gov. Chris Christie; Kentucky Sen. Rand Paul; and former Arkansas Gov. Mike Huckabee.

Romney has quietly worked to develop a kingmaker status in the Republican Party’s effort to capture a majority in the Senate this fall and win back the White House in 2016.

“I lost the election. We lost the election,” Romney said. “But I and we will continue to fight.”