Prime Minister Alexis Tsipras announced he had accepted Kotzias' resignation and said he would take over the foreign ministry himself in order "to help with all his powers in the successful completion" of the name change deal, his office said.

Kotzias's move came a day after a cabinet meeting during which he reportedly had a heated argument with Defense Minister Panos Kammenos over the name deal and felt he didn't receive sufficient support from his colleagues and the prime minister in return.

"The PM and a series of ministers made their choices in yesterday's (cabinet) meeting, and then I made mine," Kotzias said in a tweet. His resignation letter was not immediately made public.

Kammenos, who heads the governing coalition's junior party, has long objected to the deal and threatened to leave the coalition if the agreement comes to parliament for ratification.

Greece has long argued that use of the term Macedonia by its northern neighbor harbored territorial claims on its own northern province of the same name. Under the agreement, the country would change its name to North Macedonia in return for NATO membership.

But Kammenos' small right-wing Independent Greeks had vowed to oppose the deal and vote against it in parliament, which would leave the government dependent on the support of opposition parties to see it approved.

Kotzias had been angered by statements made by Kammenos during a recent trip to the United States, where the defense minister had raised the possibility of an alternate plan to the name deal — something which would go counter to current Greek and U.S. policy.

Asked earlier Wednesday during an interview on Alpha TV about reports Kotzias was deeply annoyed with Kammenos, government spokesman Dimitris Tzanakopoulos said: "I can't believe that. Because the government's policy . on (the name deal) is the policy that Mr. Kotzias agrees with. So there is no reason for discontent."

Without directly referring to Kotzias, Tzanakopoulos had previously said that "the government train is carrying on."

"Whoever doesn't want to reach the destination, or feels discontent during the journey, can get off the train," he added.

Tzanakopoulos said Tuesday's cabinet meeting involved "an open political discussion" on Kammenos' disagreement with the name deal.

"Of course we know there is a specific political disagreement that Mr. Kammenos has expressed ten months ago," he added.