Sen. John McCain (R-Ariz.) is reportedly returning to Arizona and will miss the final vote on his party's tax bill this week.

McCain, who has been hospitalized at Walter Reed Medical Center suffering from the side effects of his treatment for brain cancer, left Washington, D.C., on Sunday to return home for the holidays, CBS News reported Sunday.

This means he will not be in D.C. for the GOP tax bill vote, which is expected to take place early in the week. Republicans have won over two key votes for the measure, meaning they should still have the razor-thin majority needed to pass the bill.

The Hill has reached out to McCain's office for confirmation.

President Trump confirmed the report Sunday evening upon his return to the White House from Camp David, suggesting that McCain is willing to return to the Hill if his vote becomes key for passing the bill.

"I understand he'll come if we ever needed his vote, which hopefully we won't. But the word is John will come back if we need his vote," Trump told reporters, adding that the Arizona lawmaker is "going through very tough time."

The senator's daughter, Meghan McCain, tweeted shortly after the news broke that she and her family are "looking forward to spending Christmas together in Arizona."

"My father is doing well," she said.

Vice President Pence is delaying a trip to Israel in order to stay in Washington and ensure he can break a tie on the tax legislation vote if necessary. Republicans can only lose two votes and still have Pence act as tie-breaker.

Sen. Bob Corker (R-Tenn.) agreed this week to vote for the final bill after opposing the Senate plan. And Sen. Marco Rubio (R-Fla.) said he would support the bill after GOP leaders increased the child tax credit.

-Updated 5:31 p.m.