A heated three-day debate opened on Monday on the plan, ratification of which has been set out by the Eurozone and IMF as a condition for the continued financing of Greece, goes before the Parliament plenary.

The programme will be put to vote in Parliament on Wednesday amidst reactions by the opposition and trade unions and a 48-hour strike in protest of austerity measures and the Medium-Term programme, as well as planned privatisations of certain state utilities and organisations that was launched on Tuesday.

Discussion of the enabling law opens in Parliament's standing committee on economic affairs on Tuesday morning, to be completed the same day, while debate on the law will begin on Wednesday afternoon and completed at noon Thursday with a vote.

On the field,following weeks of protests and rolling strikes, ADEDY, the public sector union representing half a million civil servants, and GSEE, which represents 2 million private sector workers, are stepping up pressure on deputies before the votes.

As thousands rallied in Syntagma square near the parliament, hundreds of hooded youths threw stones and bottles at police who responded with teargas as the initially peaceful mood turned violent.

A street umbrella was set fire outside a record-and-book store sending black smoke spiralling into the air above Syntagma Square near the parliament.

The protesters had marched through the capital chanting slogans, banging drums and carrying banners attacking the bailout deal which many Greeks feel imposes harsh and unjust penalties on ordinary pensioners and workers while sparing the wealthy.

Transport and public services were hit, schools were shut and many shops and businesses were closed, while the streets of central Athens were virtually deserted.

A peaceful demonstration of thousands of people in Athens was soon marred by outbreaks of violence, when two groups clashed.

One side took refuge near a coffee shop, and police fired tear gas in an attempt to clear the crowds and get them out.

The situation quickly degenerated, with masked and hooded youths pelting police with chunks of marble ripped off building facades and steps. They set fire to giant parasols at an outdoor cafe, using some to form barricades, and smashed windows of a McDonalds outlet and other snack shops.

Peaceful protesters nearby braved thick clouds of tear gas to stage an outdoor street party, banging pots and pans in time to music on loudspeakers.

Staff at upscale hotels handed out surgical masks to tourists and helped them with rolling luggage past the rioting, over ground strewn with smashed-up marble and cement paving stones.

Youths torched a satellite truck parked near parliament. The fire caused a freezer at a neighboring kiosk to explode, and hooded youths ducked behind the burning truck to help themselves to ice-cream cones.

An ongoing strike by electricity company workers kept up rolling blackouts across Greece. Not far from the violent protest, cafes and ice cream vendors popular with tourists used portable generators to keep the power on.

Hundreds of flights were canceled or rescheduled as air traffic controllers walked off the job for four hours in the morning. Another walkout is scheduled for later. Strikes by public transport workers snarled traffic across the capital and left tourists stranded around Piraeus.

Thessaloniki peaceful, long lines at Evzoni border crossing

Serbia's Consul General in Thessaloníki Milan Dimitrijevic told Tanjug on Tuesday that the situation in the city, where a two-day general strike started at midnight, was peaceful and safe, and that tourists were advised to take alternative routes to avoid long lines at the Evzoni border crossing.

Dimitrijevic said state and public services, the water and electric companies, post offices and the city cleaning company had all stopped work, while public transport would stop from 9 p.m. until 8 a.m., according to information available to the Consulate.

"What affects our citizens most is the customs officers' strike at the Evzoni border crossing," Dimitrijevic said, pointing out there were long lines in both directions. Travelers are advised to head to other crossings which are not crowded at the moment.

Trucks are not allowed through at Evzoni, while passenger vehicles are occasionally allowed to cross. According to the latest information, customs officers have also started letting some buses through.

Dimitrijevic said traffic was normal at the Dojran border crossing between Macedonia and Greece, as well as at the Promahonas crossing with Bulgaria.

He said Thessaloniki was not experiencing any problems in food supply.

The consul general said the Consulate was constantly in touch with Greek authorities and had up-to-date information for Serbian tourists headed home.

Mid-term plan passed in principle by com't

The law outlining the Medium-Term Fiscal Strategy Programme's implementation until 2015 was passed by members of Parliament's standing committee on economic affairs on Tuesday, with the majority vote from ruling party MPs.

A second reading will be completed later in the afternoon, while an urgent debate and roll call vote will take place in the Parliament's plenary session on Wednesday. A vote on a related enabling law will come on Thursday.

Finance Minister Evangelos Venizelos tried to assuage (ANA-MPA) MPs fears as regards the privatisations, assuring them that Parliament will monitor the process closely.

Several ruling PASOK party MPs maintained that privatisation procedures should not be sped up, stressing that public assets should not be sold during a recession to avoid losing on their value. They referred to an inability to collect revenues, underlining that valuable time was lost and insisted on structural changes in favour of taxpayers who are hit the hardest by the austerity measures.

On their part, main opposition New Democracy (ND) party MPs said that, in principle, they will vote down the law and will present the party's position on certain articles of the draft law in Wednesday's plenary session debate. ND accused the government of being inconsistent and lacking credibility, characterising the measures unfair and ineffective.

Traffic on Bogorodica stopped, no blockades on Dojran and Medzitlija

Greek policemen and customs workers began 48-hour strike Monday midnight at the border crossings Bogorodica-Evzoni.

Greek customs workers allow passengers and cars to cross the border every 15 minutes, while international goods traffic is stopped.

Dojran - Dojrani border crossing is open for traffic. AMSM informs that still there is no traffic stoppage on Medzitlija border crossing.

There are no announcements for stoppage of cars coming from Greece travelling to Macedonia, say passengers who entered Macedonia from Dojran without any longer delays.

Interior Ministry also appeals to citizens and travel agencies to have patience and to obey the traffic regime.