President Biden condemned former President Donald Trump as "un-American" after the GOP frontrunner encouraged Russia to do "whatever the hell they want" to NATO members that did not meet spending guidelines on defense.

Biden responded to the former president from the White House on Tuesday, calling the criticism of fellow NATO member nations "shameful" and "dumb."

"The former president has set a dangerous, and shockingly, frankly un-American signal to the world," Biden said at the White House on Tuesday.

TRUMP'S NATO COMMENTS TRIGGER FIERCE MEDIA AND EUROPEAN OPPOSITION: HOW SERIOUS CAN HE BE?

BIDEN WHITE HOUSE

U.S. President Joe Biden speaks on the Senate's recent passage of the National Security Supplemental Bill, which provides military aid to Ukraine, Israel and Taiwan, in the State Dining Room of the White House in Washington, D.C. (Anna Moneymaker/Getty Images)

"When America gives its word, it means something. When we make a commitment, we keep it. And NATO’s a sacred commitment. Donald Trump looks at this as if it's a burden," the president continued.

Trump made the comments during a campaign speech Saturday in Conway, South Carolina.

The former U.S. president said "one of the presidents of a big country" once asked him whether the U.S. would still defend their country if they were invaded by Russia, even if they did not pay.

WHITE HOUSE RESPONDS TO TRUMP ENCOURAGING RUSSIA TO DO 'WHATEVER' THEY WANT TO SOME NATO MEMBERS: 'UNHINGED'

Donald Trump at a rally

Republican presidential candidate and former President Donald Trump arrives on stage during a Get Out The Vote rally at Coastal Carolina University in Conway, South Carolina.  (Win McNamee/Getty Images)

"No, I would not protect you," Trump recalled telling that country's leader. "In fact, I would encourage them to do whatever the hell they want. You got to pay. You got to pay your bills."

NATO states that an attack on one member nation is an attack on all the nations in the alliance. Trump has previously taken issue with the smaller amount of money other NATO countries spend on defense compared with what the U.S. pays. He has also threatened multiple times in the past to withdraw the U.S. from NATO.

"The whole world heard it. The worst thing is, he means it," Biden said of Trump's rhetoric, calling the statements "an invitation to Putin."

NATO logo

The NATO logo is pictured inside the North Atlantic Council meeting room at the NATO headquarters during a press tour of the facilities in Brussels. (EMMANUEL DUNAND/AFP via Getty Images)

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"No other president in our history has ever bowed down to a Russian dictator. Let me say this as clearly as I can: I never will. For God's sake, it's dumb, it's shameful, it's dangerous," he added.