Mitt Romney, who once called Trump a “phony”, now believes president-elect can lead country to a “better future”.

Republican Mitt Romney made an impassioned statement in support of President-elect Donald Trump on Tuesday in an attempt to erase doubts about him among Trump supporters and remain in contention for US secretary of state.

Romney, a fierce critic of Trump during the Republican presidential primary battle, stopped short of an outright apology but his intention to wipe the slate clean was clear.

The former Massachusetts governor, who was the Republican presidential nominee in 2012 and lost, praised Trump for a “message of inclusion and bringing people together” since his November 8 victory over Democrat Hillary Clinton.

Noting the appointments Trump has made to fill key cabinet positions for his administration and his desire for greater unity among Americans, Romney said that “all of those things combined give me increasing hope that President-elect Trump is the very man who can lead us” to a better future.

Romney made his remarks after a lengthy meal with Trump and Republican National Committee Chairman Reince Priebus at a posh French restaurant at a Trump hotel in Manhattan.

Since Trump began to seriously consider Romney as a potential secretary of state, some on Trump’s team have voiced doubts about bringing in a former critic and rallied around their preferred candidate, former New York Mayor Rudy Giuliani, a long-time Trump friend and loyalist.

Leading this effort in an unusually public way has been senior Trump adviser Kellyanne Conway, who told a round of television interviews on Sunday that Trump supporters would feel “betrayed” if Romney was picked.

New York Repuplican Congressman Chris Collins, another Trump loyalist, recently called Romney a “self-serving egomaniac”.

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“I’m all for party unity, but I’m not sure that we have to pay for that with the secretary of state position,” Conway said on CNN’s State of the Union.

“We don’t even know if Mitt Romney voted for Donald Trump,” he said.

Trump, however, has kept Romney in contention for the secretary of state position, and a Republican source close to the transition effort said Priebus has been pushing for Romney behind the scenes.

“I had a wonderful evening with President-elect Trump,” Romney said in remarks to reporters after the dinner. “We had another discussion about affairs throughout the world and these discussions I’ve had with him have been enlightening, and interesting, and engaging. I’ve enjoyed them very, very much.”

Trump is also considering US Senator Bob Corker of Tennessee, who is chairman of the Senate foreign relations committee.

Corker met Trump at Trump Tower earlier on Tuesday and told reporters afterward that Trump “needs to choose someone that he’s very comfortable with and he knows there’s going be no daylight between him and them.

“The world needs to know that the secretary of state is someone who speaks fully for the president and, again, that’s a decision he’s going to have to make.”