Former Pennsylvania Senator Rick Santorum claims that businessman Donald Trump once told him that his views on abortion and gay marriage made him a loser.

Santorum and Trump are vying for the Republican presidential nomination.

In an interview with Politico, Santorum recalled the first time he spoke with Trump.

According to Santorum, he called Trump in 2011 after Trump called him a “loser” during a television appearance.

“I'd appreciate it if you don't call me a loser,” Santorum said that he told Trump.

Trump, according to Santorum, responded: “Well, but you're too conservative. You're just out there. You're just way conservative. You're too hard-core on pro-life. You're too hard-core on marriage. I don't know anyone who shares that opinion with you.”

While Santorum is known for making unusual arguments in support of his opposition to marriage equality – such as saying gay couples cannot marry because trees are not cars – Trump once compared such unions to “an unattractive golf putter.”