Donald Trump is set to endorse House Speaker Paul Ryan (Wis.) during a rally in Green Bay, Wisconsin on Friday evening, Fox News reported.

The expected endorsement comes three days after Trump told the Washington Post he was not "yet" ready to back Ryan in his upcoming primary election next Tuesday against Wisconsin businessman Paul Nehlen.

While Trump publicly praised Nehlen for running "a very good campaign" earlier this week, Ryan is expected to win the primary by a landslide. The House speaker leads Nehlen by 66 points, according to a poll released Friday by the Remington Research Group.

Trump declined to endorse Ryan on Tuesday despite his running mate, Indiana Gov. Mike Pence, throwing his weight behind the Wisconsin congressman earlier in the day.

"I like Paul, but these are horrible times for our country," Trump told the Washington Post. "We need very strong leadership. We need very, very strong leadership. And I’m just not quite there yet."

When CNN asked Ryan in May whether he would endorse the business mogul’s presidential bid, the House speaker replied that he was "just not ready to do that at this point," although he later did announce his formal endorsement of Trump.

Ryan warned Thursday that his endorsement of Trump was "not a blank check" amid concerns in the Republican Party that the GOP nominee is making too many unforced errors rather than focusing his attacks on Hillary Clinton’s weaknesses.