Greece and Macedonia agreed last June to a deal that would change the name of Greece’s northern neighbour to North Macedonia. In exchange, Greece would lift its objections to Macedonia joining Nato.
Macedonia’s parliament ratified the deal on Friday. The Greek parliament now needs a simple majority for ratification.
Mr Tsipras’ left-wing Syriza party has 145 deputies in the 300-member Greek Parliament, while Mr Kammenos’ right-populist Independent Greeks party has seven.
Mr Tsipras could need opposition help to pass the Macedonia deal.