President Donald Trump’s threats to other countries could set the United States “on the path to World War III”, Senator Bob Corker told The New York Times on Sunday. Corker said this hours after Trump tweeted a series of sarcastic jibes against the Tennessee lawmaker.

Corker also said that Trump, who is from his own Republican Party, was treating his office like a reality show. He said a president who acts “like he’s doing The Apprentice or something” is alarming.

“He concerns me,” Corker told The New York Times in an interview. “He would have to concern anyone who cares about our nation.”

“I know for a fact that every single day at the White House, it’s a situation of trying to contain him,” he said, adding that nearly every Republican shared his concerns about Trump.

Earlier on Sunday, Corker had responded to Trump’s tweets by saying: “It’s a shame the White House has become an adult daycare center. Someone obviously missed their shift this morning.”

Trump had claimed that the senator had “begged” him to endorse him for re-election and to be secretary of state. He said he would “fully expect” Corker to block “our great agenda”. But, in his interview, Corker disputed Trump’s claim and said the president had himself urged him to run again and promised to endorse him if he did.