Marco Rubio is expected to meet Pope Leo this week, after President Donald Trump called the pontiff 'weak on crime'.
The Secretary of State, a devout Catholic, is scheduled to meet the faith leader on Thursday in Vatican City, the state department announced.
Rubio dismissed the possibility on Tuesday that the meeting would be to smooth over relations between the pope and Trump.
He told reporters during a White House press briefing: 'It's a trip we had planned from before, and obviously we had some stuff that happened', when asked about Trump's criticism of the pope.
'The trip is really not tied to anything other than the fact that it would be normal for us to engage, and other secretaries of State have done that in the past', he added.
In a fiery rant on Truth Social last month, Trump branded the leader of the world's 1.4 billion Catholics 'WEAK on Crime, and terrible for Foreign Policy'.
He then sparked controversy after posting an AI-generated image depicting himself as Jesus Christ, triggering backlash among his supporters and Catholics.
His attack came after Pope Leo called for peace in the Middle East, and said that Trump's promise to destroy Iran was 'unacceptable'.
The Secretary of State, a devout Catholic, is scheduled to meet the faith leader on Thursday in Vatican City
Pope Leo talks to journalists as he leaves his residence on the outskirts of Rome to return to the Vatican on Tuesday
On Monday night, Trump again went after the pope in an interview with conservative host Hugh Hewitt.
In it, Trump alleged that Leo believes 'it is okay for Iran to have a nuclear weapon', adding: 'I think he's endangering a lot of Catholics and a lot of people'.
The president continued: 'But I guess if it's up to the Pope, he thinks it's just fine for Iran to have a nuclear weapon.'
When asked about Trump's latest remarks on Tuesday, the pope said: 'The Church's mission is to preach the Gospel and to preach peace."
'If anyone wishes to criticize me for proclaiming the Gospel, let them do so truthfully.
'The Church has spoken out against all nuclear weapons for years, so there is no doubt about that, and I simply hope to be heard for the sake of the value of God's word.'
Trump later deleted the AI image, claiming he viewed the picture as him being a Red Cross doctor.
'Normally I don't like doing that, but I didn't want to have anybody be confused. People were confused,' he said of his removal of the image.
Trump speaks during a ceremony inside the Oval Office of the White house on Tuesday
Leo and Rubio are seen here shaking hands as they meet in the Vatican in May of last year
The President claimed that Leo, 70, was only made Pope 'because he was an American', adding: 'If I wasn't in the White House, Leo wouldn't be in the Vatican.'
He added: 'Leo should get his act together as Pope, use Common Sense, stop catering to the Radical Left, and focus on being a Great Pope, not a Politician. It's hurting him very badly and, more importantly, it's hurting the Catholic Church!'
Trump's row with the pope prompted widespread condemnation from public figures and politicians - including some of the president's allies.
Iran’s president Masoud Pezeshkian took to X in the Pope's defense, saying that he condemned 'the insult to [Pope Leo] on behalf of the great nation of Iran'.
Marjorie Taylor Greene wrote on X: 'President Trump attacked the Pope because the Pope is rightly against Trump’s war in Iran and then he posted this picture of himself as if he is replacing Jesus.'
And Italian Prime Minister Giorgia Meloni, a Trump ally, called the US president's remarks 'unacceptable'.