Anti-globalisation protesters have vowed to resume their siege of the annual meeting of the International Monetary Fund (IMF) and the World Bank in Prague this morning after a day of protests that saw demonstrators clash violently with police.

About 7,000 protesters attempted to block access to the conference centre where the meeting is being held and some demonstrators attempted to break through police barriers before being repelled with tear gas and water cannon.

Czech officials said that more than 50 police officers and 10 demonstrators were injured in the disturbances, during which a small group of protesters hurled cobblestones and petrol bombs at the police.

Last night, the protesters moved from the conference centre to surround Prague's State Opera, causing a gala performance for IMF delegates to be cancelled.

The protesters, who accuse the IMF and the World Bank of helping rich countries and multinational companies to exploit the world's poor, were preparing late last night to blockade the hotels where IMF delegates, including the Minister for Finance, Mr McCreevy, are staying.

"The fate of masses of people is being decided by unelected bankers and industrialists - 19,000 children will be dead by the end of today because of the burden of debt repayment. There's no reason for them to die because there is enough food to feed them," said an Irish member of the Socialist Workers' Party who took part in yesterday's protests and did not wish to be named.

Inside the conference centre, the IMF's managing director, Mr Horst Kohler, defended globalisation against its critics and claimed that the IMF played a positive role in helping to spread its benefits more fairly.

"I am aware of the critical debate about globalisation, and many questions raised have to be of concern to all of us.

"But I also want to be clear: if the IMF did not exist already, this would be the time to invent it. More than ever, globalisation requires co-operation, and it requires institutions which organise that co-operation."

Mr James Wolfensohn, the president of the World Bank, took a more conciliatory approach and told the conference that he had some sympathy with the protesters.

"Outside these walls young people are demonstrating against globalisation. I believe deeply that many of them are asking legitimate questions, and I embrace the commitment of a new generation to fight poverty.

"I share their passion and their question, but I believe we can move forward only if we deal with each other constructively and with mutual respect," he said.

A spokeswoman for INPEG, the group co-ordinating the protests in Prague, expressed concern that yesterday's violence, in which only a few protesters were involved, could undermine the serious purpose of the protests.

But the Irish activist cited Mr McCreevy's support for a Third World debt repayment moratorium as evidence that the protests were having an impact.

"It's at least a sign that they are feeling the pressure of the protests. This would not have happened three or four years ago," he claimed.