Thousands of Greeks took to the streets over the summer to protest the agreement over the name change, adding further pressure on Mr. Kammenos to adhere to his much-repeated line that he was ideologically opposed to the Macedonia deal.Citizens’ groups opposing that deal have called for a protest rally in Athens for Jan. 20. The main conservative opposition party New Democracy, which is far ahead of Syriza in opinion polls, also vehemently opposes the deal.The secretary general of NATO, Jens Stoltenberg, however, called it a historic moment and a victory for the Macedonian people. “NATO strongly supports the full implementation of the agreement, which is an important contribution to a stable and prosperous region,” he said.The name change must now be approved by the Greek Parliament and is expected to go to a vote this month, Mr. Tsipras said in his interview last week. Government officials have repeatedly expressed confidence that the deal will pass into law with the support of lawmakers from smaller opposition parties.Greece’s next parliamentary elections are scheduled for October 2019, and it was not immediately clear on Sunday whether two other Independent Greeks ministers, the tourism minister, Elena Kountoura, and the deputy minister for rural development, Vasilis Kokkalis, would quit the government as Mr. Kammenos did.On Sunday, Mr. Tsipras said that he had accepted Mr. Kammenos’s resignation and would also accept any other resignations, a statement widely understood as leaving the door open for ANEL ministers to remain in the leftist-led coalition.Of the six ANEL ministers, only one, deputy foreign minister Terence Quick, reacted immediately, saying he would support the government in the vote. At least two ANEL lawmakers have suggested they will back the name deal, breaking ranks with Mr. Kammenos.