In a stinging rebuke of Donald Trump, Republican Senator Bob Corker charged in an interview on Sunday that the United States president was treating his job like a "reality show," and that his rashness could set the country "on the path to World War III," The New York Times reported.

Trump acts "like he's doing 'The Apprentice' or something," Corker, the Republican chairman of the Senate Foreign Relations Committee, reportedly told the Times. The senator added he was concerned by the president's behavior, the outlet said.

Corker's support will be crucial for Trump to pass tax reform, which is the president's best and perhaps last hope for reaching a legislative landmark this year, according to the NYT.

The senator's remarks followed a caustic exchange on Twitter on Sunday in which Trump lambasted the senator for "the horrendous Iran Deal" and claimed, among other things, that Corker had "begged" him for an endorsement on a re-election.

Tweet: Senator Bob Corker "begged" me to endorse him for re-election in Tennessee. I said "NO" and he dropped out (said he could not win without...

Tweet: ..my endorsement). He also wanted to be Secretary of State, I said "NO THANKS." He is also largely responsible for the horrendous Iran Deal!

Tweet: ...Hence, I would fully expect Corker to be a negative voice and stand in the way of our great agenda. Didn't have the guts to run!

Corker responded by blasting the White House, saying it had "become an adult day care center."

Tweet: It's a shame the White House has become an adult day care center. Someone obviously missed their shift this morning.

For more on Corker's interview with The New York Times, see the outlet's full report.