Left-of-centre elements of Greece's coalition government voiced opposition on Tuesday to measures demanded by international creditors to loosen labour markets, as both sides held talks on crucial loan payments.
Fotis Kouvelis warned that the 17 deputies from his Dimar party "will not vote for the troika's" proposals if they are included in austerity measures Greece is expected to adopt in the coming days.
The troika of European Union, International Monetary Fund and European Central Bank representatives has drawn up policy measures deemed essential for Greece to straighten out its dire economic situation.
Another member of the Greek coalition government, Socialist Evangelos Venizelos, did not vow to vote against the measures but argued that Greece had already done "the maximum" in terms of loosening labour market regulations.
International creditors were "playing with fire" by requiring greater sacrifices, he said.
Talks with EU, IMF and ECB representatives nonetheless resumed late in the day, a labour ministry source said.
Greece's Finance Minister Yannis Stournaras after the meeting sought to minimise the differences, noting that "major progress realised these past few months in the discussions with the troika", stressing that there remains a "spirit of cooperation".
"There remain certain questions that we are waiting to straighten out in the next few days," he added, noting that it related to the labour marketm, but he expected the troika "to do its best to find solutions".
The labour source had said that the creditors want to abandon a regular indexation of Greece's minimum wage, which was trimmed to 580 euros early this year, along with measures to lower the cost of firing workers.
Greece's conservative-led government is in talks with the troika on an austerity package needed to unlock a loan payment of 31.5 billion euros ($41.1 billion).
The payment, which has been pending since June, is a part of the two rescue plans provided to the heavily-indebted eurozone country.
Greece has also benefited from the cancellation of more than 100 billion euros in privately held debt.
The government has presented a draft budget that foresees 7.8 billion euros in savings next year, but the county's EU/IMF/ECB auditors say measures worth 9.2 billion are needed.
European Union leaders will hold a summit this week which will discuss the negotiations with Greece.