Briarcliff Manor, New York (CNN) Donald Trump sought Tuesday to quell the intensifying criticism over his comments about the impartiality of a federal judge, saying his remarks had been "misconstrued."

In a lengthy statement, Trump tried to explain his comments about federal Judge Gonzalo Curiel , who is overseeing a lawsuit on Trump University. Trump, who had accused the Indiana-born Curiel of bias because of his Mexican heritage, said in his statement that he does not believe "one's heritage makes them incapable of being impartial."

"Based on the rulings that I have received in the Trump University civil case, I feel justified in questioning whether I am receiving a fair trial," Trump said.

He added that he also has "concerns as to my ability to receive a fair trial" due to his status as the Republican Party's presumptive nominee and his campaign's focus on illegal immigration.

"Normally, legal issues in a civil case would be heard in a neutral environment. However, given my unique circumstances as nominee of the Republican Party and the core issues of my campaign that focus on illegal immigration, jobs and unfair trade, I have concerns as to my ability to receive a fair trial," Trump said, adding that he does "not intend to comment on this matter any further."

Trump showed signs already in an interview Monday night with Fox News' Bill O'Reilly that he was softening his position on the judge as he seemed to downplay his past criticism of Curiel.

"I don't care if the judge is Mexican or not," Trump told O'Reilly. "All I want him to do is give me a fair shake."

Trump's statement Tuesday represented a cooling of previous criticism he has lobbed at Curiel, but it did not include an apology or an expression of regret.

Despite saying that he does not believe a judge's heritage "makes them incapable of being impartial," Trump continued to insist in his statement Tuesday that the questions he raised about Curiel's impartiality were "fair."

Trump last week repeatedly took aim at Curiel, calling him a "hater" and "a Mexican" as he slammed the judge's rulings in the case.

Trump's statement Tuesday came amid a barrage of criticism from both Democrats and Republicans who widely condemned Trump's comments as inappropriate, inexcusable and some even characterized the remarks as racist.

House Speaker Paul Ryan on Tuesday offered a particularly harsh condemnation of Trump's words, calling them "sort of like the textbook definition of a racist comment."

"I think that should be absolutely disavowed. It's absolutely unacceptable," Ryan said Tuesday morning.

And Republican Sen. Mark Kirk on Tuesday became the first major Republican to rescind his endorsement of Trump, saying he his party's presumptive presidential nominee "does not have the temperament" to hold the job of president and that he "cannot and will not support" Trump.

"Given my military experience, Donald Trump does not have the temperament to command our military or our nuclear arsenal," he tweeted.

Given my military experience, Donald Trump does not have the temperament to command our military or our nuclear arsenal. — Mark Kirk (@MarkKirk) June 7, 2016

Trump's statement Tuesday also came after the presumptive GOP nominee spoke with his party's chairman Reince Priebus, a Republican source told CNN.

One of Trump's top supporters, New Jersey Gov. Chris Christie, left Trump Tower Tuesday without commenting to reporters when asked about the controversy.

Trump had already begun facing sharp criticism from other powerful Republicans, including Senate Majority Leader Mitch McConnell who called Trump's remarks "offensive and wrong."

Other Republican senators followed suit in condemning Trump's racial attack on the judge and the criticism also extended to longtime Trump allies.

Former House Speaker Newt Gingrich, who had been floated as a potential running mate for Trump, called Trump's comments about the judge "inexcusable" and "one of the worst mistakes Trump has made."

Sen. Jeff Sessions, the first sitting senator to endorse Trump earlier this year, refused to defend Trump's remarks and Sen. Bob Corker, who has met with Trump several times, called Trump's comments "wrong" and told CNN Tuesday that the Republican nominee has two to three weeks "to redirect their efforts in a positive way."

Former rival Jeb Bush implied Trump's statement was lacking, tweeting: "Donald Trump should retract his comments, not defend them. There is no place for racism in the GOP, or this country."