Athens faced major traffic jams Monday as trade unions proceeded with a 24-hour stoppage of commuter train and bus services ahead of parliament's vote on measures demanded by Greece's creditors.

Air traffic controllers also planned a three-hour stoppage from midday local time.

Parliament's vote, due late Monday, is regarded as the potentially last major package of cuts before a long-running international bailout program ends in August.

The bill, which would allow strikes only when a union musters a 50-percent vote at a members' assembly, again puts Prime Minister Alexis Tsipras and his nominally left-wing Syriza party on collision with organized labor.

Currently, the threshold is as low as 20 percent, and, reportedly in some cases strikes can be called by union executives alone.

'We won't stop'

"Let them vote for whatever they like. We won't stop," said Giorgos Perros, a Greek Communist Party member and a lead organizer of a similar protest staged last Friday.

Government spokesman Dimitris Tzanakopoulos last Friday said the amendment to a 1982 law on strikes was minor, adding "it does not change the process."

Greece's leading GSEE, however, said the bill dealt a blow to workers, pensioners and the unemployed by removing constitutionally safeguarded rights.

Strictures

Under bailout reviews - overseen by the EU and International Monetary Fund (IMF) – Tsipras' coalition also agreed in December to further cut spending, reduce pensions, evaluate public sector staff skills and sell coal-fired power stations.

His term ends in 2019 and his Syriza party is trailing Greece's New Democracy party in opinion surveys.

Returning to market?

From August on, Greece intends to finance its borrowings on the open market and without bailout provisions.

The yield on Greece's 10-year bond had dropped last week to below 4 percent - its lowest in more than a decade – signaling that investors were more hopeful.

Greece has seen some 50 general strikes since its economic crisis began in 2010.

Its economy lost about a third of its output – measured over a seven-year period – and its budget for 2018 forecasts growth of 2.5 percent for 2018.

ipj/ng (Reuters, dpa, AP, dpa)