(CNN) - President Donald Trump announced on Friday that his ambassador to Japan, Bill Hagerty, would run for the US Senate in Tennessee with his "Complete & Total" endorsement.
"Tennessee loving Bill Hagerty, who was my Tennessee (Victory) Chair and is now the very outstanding Ambassador to Japan, will be running for the U.S. Senate," Trump tweeted. "He is strong on crime, borders & our 2nd A. Loves our Military & our Vets. Has my Complete & Total Endorsement!"
CNN reported earlier in the day that Hagerty was considering launching a 2020 campaign. He has not yet made a formal announcement himself.
Sources said Hagerty is widely expected to enter the race after two prominent Tennessee Republicans -- former Gov. Bill Haslam and Rep. Mark Green -- announced on Thursday that they would not run for Senate.
"I expect Bill to run," Green told CNN. "All the indications are that he's going to run."
Haslam's announcement in particular cleared a path for Hagerty to run for the seat left open by the retiring Republican Sen. Lamar Alexander.
Hagerty, who served under Haslam as commissioner of the state's Department of Economic and Community Development, would likely not run against his old boss. But he positioned himself to launch a campaign if Haslam passed, reaching out to Tennessee politicos and returning to the state for Gov. Bill Lee's inauguration in January and the state GOP's annual Statesmen's Dinner in June.
"He's called people for months all over the state," said a Tennessee Republican official. "Just about everybody has received a call from Bill saying he's interested."
Nashville orthopedic trauma surgeon Manny Sethi, a Republican, has already announced his candidacy. Rep. David Kustoff and former Rep. Stephen Fincher have said they're considering entering the race too.
But Alexander told CNN that Hagerty would benefit in a primary from his "close" relationship with President Donald Trump. A source familiar with the matter told CNN that Hagerty also maintains a positive relationship with Trump's daughter and adviser Ivanka.
"He's in a great spot with the President," Green said. "He's a very interesting candidate because he can bridge the conservatives and the establishment."
Hagerty and the State Department did not respond to CNN's request for comment.
During the 2016 presidential campaign, Hagerty worked to elect Trump and then served on the transition team before the Senate overwhelmingly confirmed his nomination in July 2017. He served in the George W. Bush administration as a staffer focusing on trade.
In addition to his time as a public servant, Hagerty spent years working in the private sector and founded his own private equity investment firm.
Amid some reports that Secretary of State Mike Pompeo was considering running for a US Senate seat in Kansas -- despite saying he ruled it out earlier this year -- some considered Hagerty to be a possible contender to replace him as the top US diplomat, according to a source familiar with the situation.
Pompeo's own future remains unclear. Senate Majority Leader Mitch McConnell, a Kentucky Republican, noted on Wednesday that he would like him to run for Senate, but the source said it is unlikely that Hagerty would wait for Pompeo to make a decision before assessing his own opportunity.
As ambassador, Hagerty has helped facilitate several high-profile visits to Japan by Trump and other top US officials, including last month's trip for the G20 summit. When then-acting Defense Secretary Patrick Shanahan visited the country earlier in June, Japanese officials publicly credited Hagerty with helping to strengthen ties between the two countries.
This story has been updated with additional developments Friday.