Donald Trump, the Republican presidential candidate, has thrown doubt on NATO before but never outright said he might allow Russia to invade a Baltic state — until now.

The property tycoon and former television star, who is due to be nominated by his party later on Thursday, told The New York Times he would only come to the aid of an ally if they had “fulfilled their obligations” to the United States.

He was asked specifically about a possible Russian attack on one of the three Baltic nations, which freed themselves from Soviet rule in 1990.

It’s unclear what obligations he meant.

Trump is the first presidential candidate to call into question America’s willingness to meet its mutual defense commitments under the North Atlantic Treaty of 1949.

Putin’s stooge

Jeffrey Goldberg, a foreign-policy journalist, argues in The Atlantic that Trump is doing Russian president Vladimir Putin’s work for him in weakening allied solidarity.

Equivocating, mercenary statements like Trump’s, he writes, “represent an invitation to Putin to intervene more destructively in non-NATO countries such as Ukraine and Moldova and also represent an invitation to intervene directly in NATO countries — the Baltic states, first and foremost.”

Goldberg fears — with reason — that a Trump presidency would end the postwar international order and liberate dictators, like Putin, to advance their interests.

Trump has praised Putin in the past as a strong leader and seems unperturbed by the Russian’s attempts to reduce American influence in Europe and undermine the liberal world order America built in the aftermath of World War II.