Story highlights Newt Gingrich criticized Donald Trump's comments of a judge who's handling his Trump university case

The presumptive GOP nominee responded Monday saying the former House Speaker's remarks were 'inappropriate'

(CNN) Donald Trump jabbed Newt Gingrich on Monday after the former House Speaker criticized the presumptive GOP nominee for attacking the federal judge overseeing the Trump University lawsuit, saying his critique was "inappropriate."

Appearing on "Fox and Friends," Trump said he'd heard Gingrich's comments about him and "was surprised at Newt. I thought it was inappropriate what he said."

Gingrich, who has drawn scrutiny as a potential vice president pick, joined a chorus of top Republicans rebuking Trump for repeatedly accusing U.S. District Judge Gonzalo Curiel, overseeing a lawsuit involving Trump University, of bias because of his Mexican heritage. Those concerns intensified Sunday after Trump said he would have the same concerns about the impartiality of a Muslim judge.

In an interview with the Washington Post , Gingrich said "I don't know what Trump's reasoning was, and I don't care. His description of the judge in terms of his parentage is completely unacceptable." And on "Fox News Sunday," he said that it was "one of the worst mistakes Trump has made," adding: "I think it's inexcusable."