Greeks set to strike as MPs debate austerity measures

Demonstrators say they will encircle the parliament building in an attempt to prevent MPs from taking part.

Prime Minister George Papandreou is trying to push through fresh policies as part of the conditions for the EU and IMF's bail-out package.

A top credit agency has cut Greece's rating, making it the least credit-worthy country of 131 it monitors.

The Greek government said the downgrade by Standard & Poor's - from B to CCC - ignored its efforts to secure funding.

Activists and unionists plan to gather at Syntagma Square on the front steps of the assembly in central Athens on Wednesday.

Mr Papandreou faces the risk of a backbench revolt over the plans.

One MP defected from Mr Papandreou's PASOK party defected on Tuesday, leaving it with only 155 of the chamber's 300 seats.

"You have to be as cruel as a tiger to vote for these measures. I am not," George Lianis, a former sports minister, said in a letter to parliament's speaker announcing his departure from the parliamentary group.

At least one other Socialist MP has threatened to vote against the new programme of cuts and privatisation of state assets.

The government has appealed for consensus over its proposals, which would see 6.5bn euros (£5.7bn; $9.4bn) worth of tax rises and spending cuts this year.

"Every Greek, particularly the new generation, demands that we fight the battle with all our power, a battle to avoid a disastrous bankruptcy which will undermine the future of the country," government spokesman George Petalotis told reporters.

"We are fighting the battle to serve the common good, in the most crucial moment in the country's modern democracy."

The EU and IMF is demanding the measures in return for the release of another 12bn euros in aid next month which Athens needs to pay off maturing debt; Kazinform cites BBC.