Trump pays tribute to late Sen. Lindsey Graham

US President Donald Trump paid tribute Monday to the late Sen. Lindsey Graham, describing the South Carolina Republican as a "fantastic man."

Speaking to reporters at the White House, Trump said he had spoken with Graham shortly before the senator's death and recalled that he had appeared to be in good spirits despite feeling fatigued.

"I want to pay my respects to Sen. Lindsey Graham, who was our friend. He was a friend of all of us," he said. "He was a great guy. He was a great politician, actually. And it's hard to believe he's gone."

The president said Graham had called him after returning from Ukraine simply to check in.

"I spoke to him just before he passed away, just to say hello. He got back. He felt fine. He was a little tired, and then this whole thing happened," Trump said. "It's tough."

Trump announced that flags across the country would remain at half-staff until Saturday evening, calling the extended tribute appropriate for Graham's legacy.

"He was very much in favor of the Save America Act. He called me about that. We were talking about that and some other things, but he just felt tired. But he felt fine, and then this horrible thing happened just a short time afterwards. So it was terrible," he said.

South Carolina Gov. Henry McMaster appointed Graham's sister, Darline Graham Nordone, to temporarily fill the vacant Senate seat following the senator's death late Saturday.

Nordone, whom Trump endorsed as his preferred choice for the appointment, is expected to be sworn in as early as this week. She will serve the remainder of Graham's current term through January, restoring Republicans to their full 53-47 Senate majority.

A separate Republican special primary is scheduled for August to select the party's nominee for the subsequent full six-year Senate term.

The vacancy had briefly narrowed Republicans' working majority. With Sen. Mitch McConnell absent due to illness and Graham's seat unfilled, Republicans were effectively operating with a 51-seat caucus, potentially complicating Senate Majority Leader John Thune's efforts to advance key legislation, including the annual defense policy bill.