ATHENS (Reuters) - Flights were disrupted and hospitals ran on skeleton staff in Greece on Thursday in a strike called by public-sector workers against the pension and tax reforms sought by Greece’s foreign lenders.

Thursday’s 24-hour walkout called by public sector union ADEDY coincides with a review by lenders of Athens’s compliance with terms of an international bailout agreed last year.

Greeks have seen their incomes and services slashed under austerity measures agreed as part of its international bailouts.

European Union institutions and the International Monetary Fund are holding out for a conclusion of additional reforms by Athens before signing off on the review, which could potentially unlock further financial aid to the indebted country.

“Our strike is just a warm-up, we will stage a 48-hour strike when the government submits the bill (to parliament) with the measures,” said Odysseas Drivalas, member of ADEDY’s executive board.

“Workers have lost almost half of their income since the crisis started, they cannot bear any more of this burden. With labor action, we can at least put pressure on them (the government).”

ADEDY represents about 500,000 public sector workers and pensioners.

The review of Greek fiscal reforms has stalled for weeks because of disagreements between European Union institutions and the IMF on the level of fiscal adjustment Athens must pursue to cover any shortfalls, the form future debt relief should take, and Athens’s recalcitrance in targeting pensions to trim spending.

Government officials say they hope for a draft agreement in place by this coming Sunday.

Debt relief is an integral part of the strategy of Prime Minister Alexis Tsipras to convince Greeks their sacrifices over six years of recession are finally paying off.

Port workers were expected to walk off the job on Friday, to protest the sale of the country’s largest port, Piraeus Port to a Chinese shipping giant. Privatizations are also part of the bailout deal.