Former President George H.W. Bush will formally endorse Mitt Romney’s presidential bid on Thursday, becoming the latest establishment Republican to rally behind the GOP frontrunner.

In this Dec. 1, 2011 file photo, Republican presidential candidate, former Massachusetts Gov. Mitt Romney meets with former President George H.W. Bush in Houston. (Pat Sullivan/AP)

Romney spokeswoman Andrea Saul confirmed that Bush and Romney will huddle privately in Houston on Thursday and that the 41st president is expected to make his endorsement of the former Massachusetts governor at a joint event following the meeting. News of the endorsement was first reported by the Associated Press.

For months, there had been signals that a Bush endorsement of Romney might be in the works. In an interview with the Houston Chronicle in December, the former president offered strong words of encouragement for Romney, although he stopped short of officially backing him in the GOP race.

The two have also had a long personal friendship, and in December 2007, Romney delivered an address on his Mormon faith at the George Bush Presidential Library in College Station, Texas.

The endorsement also comes as other members of the Bush clan have thrown their support behind the former Massachusetts governor. Bush’s wife, former first lady Barbara Bush, recorded robocalls for Romney earlier this month in the primary states of Ohio and Vermont.

And former Florida governor Jeb Bush last week announced his endorsement of Romney, arguing that “now is the time for Republicans to unite behind Governor Romney and take our message of fiscal conservatism and job creation to all voters this fall.”

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