Trump calls Pelosi 'Nervous Nancy' before a somber D-Day commemoration in Normandy where 20,000 troops died 75 years ago

David Vincent/AP Images

President Donald Trump stands with World War II veterans during a ceremony to mark the 75th anniversary of D-Day at the Normandy American Cemetery in Normandy, France.

• President Donald Trump took a shot at House Speaker Nancy Pelosi during a Fox News interview in Normany, France on Thursday shortly before he attended a commemoration of the 75th anniversary of D-Day. 
• "Nancy Pelosi, I call her Nervous Nancy, Nancy Pelosi doesn't talk about it. Nancy Pelosi is a disaster, okay?" Trump said. "She's a disaster. Let her do what she wants, you know what? I think they're in big trouble."
• Pelosi refused to take the bait - at least for now. "I don't talk about the president while I'm out of the country. That's my principle," she said Thursday. 
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President Donald Trump took a shot at House Speaker Nancy Pelosi during a Fox News interview in Normandy, France on Thursday shortly before he attended a commemoration of the 75th anniversary of D-Day. 

Sitting in front of a cemetery of American war dead, Trump argued that Pelosi's leadership and the Democratic party's investigations into him are a "disaster." And he took the opportunity to debut a nickname for Pelosi. 

"Nancy Pelosi, I call her Nervous Nancy, Nancy Pelosi doesn't talk about it. Nancy Pelosi is a disaster, okay?" Trump said during an interview with Fox host Laura Ingraham. "She's a disaster. Let her do what she wants, you know what? I think they're in big trouble."

When asked about the comment, Pelosi, who is also in Normandy, told reporters that she has a policy of not criticizing the president while she's on foreign soil. 

"I don't talk about the president while I'm out of the country. That's my principle."

Read more: 'Impeachment is inevitable': More Democrats push for impeachment as Nancy Pelosi accuses Trump of 'engaging in a cover-up'

Pelosi and Trump have traded increasingly personal attacks over the last few weeks, as pressure from Democrats builds to initiate an impeachment inquiry into the president. 

"In plain sight, in the public domain, this president is obstructing justice, and he's engaged in a cover-up, and that could be an impeachable offense," Pelosi said late last month, prompting Trump to abruptly cancel a meeting with Democratic leadership. 

On Wednesday, Pelosi told senior Democratic lawmakers she wants to "see [Trump] in prison," Politico reported.