Britain's Prime Minister Gordon Brown and the United Nations Secretary-General Ban Ki-moon publicly backed Afghan President Hamid Karzai on Saturday in Port of Spain, the capital of Trinidad and Tobago.

Speaking at a press conference at the sidelines of the Commonwealth Heads of Government Meeting (CHOGM), the two leaders committed to two conferences on Afghanistan -- one in London in January and the other in Kabul, for which no date was given.

Britain's Prime Minister Gordon Brown (L) and U.N. Secretary General Ban Ki-moon attend a press conference during the Commonwealth Heads of Government Meeting (CHOGM) in Port-of-Spain November 28, 2009. [Xinhua]?

"The United Nations is looking forward to working with Afghanistan's President Karzai," Ban told media. "This morning I spoke with Gordon Brown about a planned conference in London followed by a similar one in Afghanistan."

Ban said that it offered opportunities for high level discussions between all those interested in Afghanistan's issues.

Brown said that Britain may commit a further 9,500 troops to Afghanistan, but would only do so if the nation showed signs of progress against corruption and more stable institutions.

"I have a duty to the British people to prevent terrorism from reaching British streets and the best way to do that is to make sure Afghanistan is stable," Brown told media.

"The UK is prepared to raise troop numbers to 9,500 but conditions have to be met," he said.

The Afghan government must supply troops to collaborate with international forces and be trained by their British counterparts and British troops must be properly equipped, he said.

Brown also said that Britain would push Afghanistan to fight corruption at local and national level, raising standards after an election that many reporters said included elements of fraud.

"Ever since President Karzai was inaugurated he has promised an anti-corruption task force which will lead to anti-corruption laws," Brown told media. "A lot is being done to fight corruption in Afghanistan."

The Port of Spain meeting brought together 51 heads of state from nations most of which were former British colonies and Ban flew in to address a special plenary session on climate change on Friday, a highly unusual move which takes place when there are just a few days before the COP15 conference in Danish capital Copenhagen that is set to find a new agreement to replace 1997's Kyoto Protocol.

The meeting has attracted a total of 5,000 delegates to Port of Spain, including government officials, non-government organization workers, business people, media and representatives of youth organizations.?