GOP nominee Donald Trump went on a Twitter tirade against Speaker of the House Paul Ryan Sunday, just one day before the billionaire is slated to campaign in the Wisconsin Republican’s home state.

Trump, who is set to appear in Green Bay, Wis., Monday, has repeatedly attacked Ryan since the speaker said he would not campaign with him. Ryan instructed Republican lawmakers to do what is best for them and their districts in an attempt to keep the majority in Congress.

Trump attacked the 2012 vice presidential nominee as “a man that doesn’t know how to win,” alleging he is working against him in the election.

The Democrats have a corrupt political machine pushing crooked Hillary Clinton. We have Paul Ryan, always fighting the Republican nominee!

— Donald J. Trump (@realDonaldTrump) October 16, 2016

Paul Ryan, a man who doesn't know how to win (including failed run four years ago), must start focusing on the budget, military, vets etc.

— Donald J. Trump (@realDonaldTrump) October 16, 2016

Wow, interview released by Wikileakes shows "quid pro quo" in Crooked Hillary e-mail probe.Such a dishonest person – & Paul Ryan does zilch!

— Donald J. Trump (@realDonaldTrump) October 16, 2016

Ryan’s office disputed Trump’s repeated claims the election is rigged in favor of Democratic nominee Hillary Clinton Saturday.

“Our democracy relies on confidence in election results, and the speaker is fully confident the states will carry out this election with integrity,” Ryan spokeswoman AshLee Strong told BuzzFeed.

Despite the attacks, the speaker’s endorsement of Trump remains intact and he has stated he is committed to helping down-ballot candidates get re-elected.

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