The UN has urged government ministers at a major environmental meeting to match their words with deeds as delegates continued to fight over a proposed action plan.

"Governments must make good on their commitments," UN Deputy Secretary-General Louise Frechette said at the summit in Bali, Indonesia.

"The challenge as ever is to match aspiration with action."

Delegates and ministers from more than 170 countries are meeting on the resort island, trying to agree on an action plan ahead of August's massive World Summit for Sustainable Development in Johannesburg.

There have been several small protests

Senior ministers joined the meeting on Wednesday, but their lower-level officials have made little headway since starting preliminary negotiations more than a week ago.

The wide-ranging talks cover issues such as plans to cut poverty and pollution, as well as a proposal to double the number of people around the world with sanitation and drinking water by 2015.

The UN says 1.1 billion people around the world have little or no access to safe drinking water, and that 2.2 million people - many of them children - die of various diseases as a result each year.

US opposition

The European Union Environmental Commissioner, Margot Wallstrom, said delegates from the United States and some other countries have opposed moves to commit to targets and timetables in the action plan.

The BBC's Richard Galpin in Bali says that the conference may not even reach an agreement by Friday.

The meeting comes on World Environment Day, and 10 years after the first Earth Summit in Rio de Janeiro, Brazil.

But some environmental campaigners say the world's environmental health has gone downhill since then.

Hira Jamtani, a leading Indonesian environmentalist, says this is partly because Western countries have not fulfilled pledges to help developing nations eradicate poverty - the cause of much environmental destruction.

Between 200 and 300 Indonesian protesters outside the meeting sang songs and chanted slogans against the United States and other rich countries, accusing them of doing too little to help the world's poor.

Indonesian President Megawati Sukarnoputri told delegates in a speech on Wednesday that rich and poor nations must co-operate to solve environmental problems.