Donald Trump says he will sue [crscore]Ted Cruz[/crscore] if his rival for the Republican nomination for president doesn’t “doesn’t take down his false ads and retract his lies” about him.

The New York businessman made his threat in a news release before reiterating his comments during a press conference in South Carolina on Monday.

After calling Cruz “unstable,” Trump said: “One of the ways I can fight back is to bring a lawsuit against him relative to the fact that he was born in Canada and therefore cannot be president. If he doesn’t take down his false ads and retract his lies, I will do so immediately.”

Trump, in recent weeks, has taken aim at Cruz for being born in Canada, saying that means he is not a natural born citizen and therefore unable to serve as president. Cruz, pointing out that his mother was American when he was born, says he is eligible.

Earlier on Monday, Cruz’s campaign released an ad saying voters “cannot trust Donald Trump” to nominate conservative justices to the Supreme Court.

“Ted Cruz is a totally unstable individual,” Trump said. “He is the single biggest liar I’ve ever come across, in politics or otherwise, and I have seen some of the best of them. His statements are totally untrue and completely outrageous.”

Trump added: “It is hard to believe a person who proclaims to be a Christian could be so dishonest and lie so much.”

Trump countered Cruz’s argument about the Supreme Court by noting that he specifically mentioned two conservative judges recently when discussing the types of people he would nominate to the court.

“Cruz said I would be appointing a liberal judge when in fact I will appoint a great conservative and I am the only candidate who has gone so far, at the debate, as to suggest two individuals I feel would best represent the conservative values we need to protect: William ‘Bill’ Pryor Jr. and Diane Sykes,” Trump said.

Trump also took issue with other types of criticism from Cruz:

Cruz says I am pro-choice, when in fact I am staunchly pro-life and have been for a long time. Like Ronald Reagan, on many issues, I have evolved. Cruz says I am in favor of ObamaCare, when in fact I have spoken about repealing and replacing this disaster of a system at every speech throughout my campaign and since its inception. Meanwhile, Cruz was responsible for getting Bush to put in the judge that failed to vote against ObamaCare twice. Cruz says I will try to take away your second amendment rights, when I am one of the strongest proponents of the right to bear arms and I say so in every speech that I have made for years. I am a proud member of the NRA and so are my sons.

Trump added: “Cruz has become unhinged and is lying with the hopes that his statements will go unchecked until after the election and he will save his failing campaign.”

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