Greek unions protest against PM's austerity plans
Greek unions have staged mass protests in the city of Thessaloniki against the government's austerity programme.
The protests were largely peaceful but police used tear gas on a small group which broke away from the rally.
But Prime Minister George Papandreou, who is attending a trade fair in the city, has said he is not going to give up on his government's austerity plans.
On Friday, the government said there would be further austerity measures, in addition to those already announced.
Some 20,000 people marched through Thessaloniki to protest against Mr Papandreou's swingeing cuts, which have already had a significant impact on public spending.
The country's trade unions have said they believed the government wanted to "overthrow" workers' rights, on top of cutting public sector wages and pensions.
The march was largely peaceful but minor clashes were reported and police fired tear gas at a small group which broke away from the main rally.
Mr Papandreou said he would not be swayed by the demonstrations and that he was "not thinking of the political cost".
"We are fighting for the survival of Greece. Either we'll win together, or we'll sink together."
"I ask all the country's productive forces to join us, to support this great change."
Earlier on Saturday, a shoe was thrown at Mr Papandreou, although landed wide of its target.
Dr Stergios Prapavezis, a respected local cancer specialist - was detained along with his 15-year-old daughter and Stavros Vitalis, a farmer with whom he set up a protest movement called the Patriotic Front.
Before the incident, Dr Prapavezis had told the BBC that the prime minister was not welcome in the northern region because he had surrendered Greece's sovereignty and subjected ordinary people to poverty.
The BBC's Malcolm Brabant in Thessaloniki says that with 3,000 police patrolling the city's streets, the fact that a single shoe thrower got so close to the prime minister will be a source of major embarrassment.
The centre-left government imposed a tough austerity programme in May in return for a 110bn-euro ($140bn; £91bn) bail-out from the International Monetary Fund (IMF) and the European Union that helped it stave off bankruptcy.
On Friday evening, Finance Minister George Papaconstantinou said it was on track to reduce its budget deficit from 13.6% of GDP in 2009 to 8.1% this year, and pledged to maintain the pace.
"We will continue as we started," he was quoted as saying by the Associated Press news agency.
"[However,] several more months must pass before we can convincingly show that what has been done was not a flash in the pan, and that we won't fall to pieces at the first sign of hardship."
Mr Papaconstantinou said he planned to overhaul several state-run corporations including the Greek Railway Company, which has 10.7bn euros of debts.
"As a society, we have shown that we understand the problem," he said.
The government also wanted to introduce reforms in the tourism, education, agriculture and energy sectors in the coming year, he added.
Official figures published earlier this week showed the contraction of the Greek economy was accelerating. It is expected to shrink by 4% this year.
Inflation has also reached 5.5% - its highest level in more than a decade - and more than half a million people were officially out of work in June.