Greece's leftwing-led government is entering a new round of negotiations with its creditors over progress on the latest bailout program, amid angry union reactions to proposed pension reforms — a key part of the talks.

Representatives of Greece's European creditors and the International Monetary Fund are due to meet the country's finance minister later Monday. Greek officials say there will be a break in the talks at the end of this week, but it is unclear how long that will last.

Following pressure from bailout creditors, the government has committed to overhaul the country's pension system, which, it admits, is otherwise moribund.

But unions representing groups as disparate as farmers, police, fishermen and lawyers fiercely oppose the draft reforms, and plan a string of protests and strikes this week.