The two-day Asia-Europe Meeting (ASEM) involving 43 nations which began Monday was overshadowed by clashes between police and an estimated 4,000 left-wing demonstrators.

An estimated 4,000 anti-globalization protesters marched toward the summit venue, using it to gear up for next month's demonstrations at the G8 economic summit. Police, however, stopped the protestors before they reached the ASEM hotel meeting location.

Later, hundreds of far-left demonstrators wearing ski masks built a barricade and set it ablaze in an area of Hamburg known as a hub for radical leftists.

A police spokesperson said police extinguished the fire and arrested at least 21 demonstrators on suspicion of violence including attacks on security officers and making firebombs. At least 30 other protestors were detained.

Police said one police officer and a female protester were hurt, 21 demonstrators were arrested and a further 30 detained.

Warming up for the G8

Demonstrators -- including radicals from several European nations -- were said to be using the event as a "practice run" for the upcoming Group of Eight summit to be hosted by Germany from June 6-8 at the northern beach resort of Heiligendamm.

On Saturday, German Chancellor Angela Merkel spoke out in support of the right to demonstrate peacefully and voiced sympathy for environmentalists' calls for deep cuts in emissions, one of her key demands at the G8 summit.

German authorities, who were likewise treating Monday's event as practice for next month, said they would crack down hard on any rioting. Monday's demonstrators found themselves marching between a cordon of riot police accompanying the procession.

Organizers voiced frustration at the cordon and said that police barriers made it difficult for crowds to disperse following the event.

But German Foreign Minister Frank-Walter Steinmeier rebuked the demonstrators.

"The protesters have a right to demonstrate. They have a right to raise the issues," said Steinmeier who was hosting the foreign ministers' talks as part of the German presidency of the EU.

"But I would like to ask them a question back. Why do they

demonstrate against a conference where Asians and Europeans try to establish a shared view on the places of conflict in this world?

"When we have so many places of conflict, we are duty bound to try to find a solution in a spirit of partnership,' he insisted, then adding: "We are trying."

Big impact

In his opening remarks for the meeting, Steinmeier said: "We in the Asia-Europe Meeting represent about 50 percent of gross domestic product, 58 percent of the global population and 60 percent of international trade."

ASEM, held every two years, offers ministers or their deputies a chance to talk and does not take any formal decisions. India, Pakistan and Mongolia are attending for the first time. There is discord between European countries seeking deep cuts in world carbon-dioxide emissions and Asian governments countering that they have not caused global warming,

The three working sessions Monday and Tuesday are expected to cover issues ranging from crises with Iran and North Korea to anti-terrorism policies.

On Monday in Hamburg, Myanmar Foreign Minister Nyan Win defended his government's one-year extension of house arrest for Nobel Peace laureate Aung San Suu Kyi, telling Japanese Foreign Minister Taro Aso that it had been "a very difficult decision."

A Japanese Foreign Ministry spokesman said that Win had explained that the Myanmar military junta had been concerned with both "political stability" and negative reactions from the international community.

Earlier, after an advance meeting with Chinese Foreign Minister Yang Jiechi, German Foreign Minister Steinmeier said that he remained hopeful that agreement on emissions reductions could be reached with China before a world summit on global warming in December in Bali.

Voicing a sentiment shared by many Asian nations, which oppose sharp cuts, Yang said that China already had its own targets and made clear that Beijing believes it is up to industrialized countries to cut world emissions.

"China is a developing country, and per capita emission of greenhouse gases in China is much lower that in developed nations," he said.

Darfur crisis

In a bilateral meeting with China, the European Union pressed Beijing to open its markets to help redress a "huge" trade surplus with the bloc and appealed to the country to ratify a key rights covenant that also covers labor rights.

France, for its part, used the meeting to propose opening a humanitarian corridor through Chad to bring relief to victims of the Darfur conflict, French Foreign Minister Bernard Kouchner said late Monday.

The Sudanese government has repeatedly rejected plans to deploy UN troops alongside the African peacekeepers in a joint force numbering some 23,000 soldiers.

Khartoum's hand has been strengthened by China, which has opposed US-led plans within the UN Security Council to use sanctions to force President Omar al-Beshir to accept a UN force.

Kouchner spent an hour in one-on-one talks with Yang on the sidelines of the ASEM meeting in a bid to bring China fully on board in efforts to resolve the Darfur crisis.