Obama says he wants to 'finish the job' in Afghanistan
Barack Obama: "We are going to dismantle and degrade" al-Qaeda's capabilities
US President Barack Obama has said it is his intention to "finish the job" in Afghanistan after eight years of conflict there.
Mr Obama said he would announce a long-awaited decision over sending more troops to Afghanistan "shortly".
Some US media reports have suggested that the US president is intending to send 34,000 more troops.
He has been considering a request from his top commander in Afghanistan for 40,000 more US troops.
Mr Obama said a continuing review of US policy in Afghanistan had been "extremely useful", stressing that it was in the US strategic interest to make sure al-Qaeda and its allies could not operate in the area.
"We are going to dismantle and degrade their capabilities and ultimately dismantle and destroy their networks," he said.
"After eight years, some of those years in which we did not have, I think, either the resources or the strategy to get the job done, it is my intention to finish the job."
If he does decide to increase troop numbers, the reaction from his own party will be all important
Speaking at a press conference with Indian Prime Minister Manmohan Singh, he added that the Afghan people were "going to have to provide ultimately for their own security".
Mr Obama is widely expected to announce his decision on US troop reinforcements in Afghanistan in a prime-time TV address next Tuesday.
"I feel confident that when the American people hear a clear rationale for what we're doing there and how we intend to achieve our goals, that they will be supportive," he said.
BBC North America editor Mark Mardell says that some within the president's own party will not be happy if he does announce a substantial increase in troop numbers.
But there is every sign he will put a great deal of effort into also explaining how and when the Afghan mission will end, he says.
The president has been saying with increasing frequency that a key part of the rethinking of the US Afghanistan strategy involves building an exit strategy into the announcement.
In his comments on Tuesday, Mr Obama said "the whole world" should help with the US-led Afghan mission, and that he would speak in his announcement of "the obligations of our international partners in this process".
The US currently has about 68,000 troops in Afghanistan, which contribute to total foreign forces of more than 100,000.
In Britain, Defence Secretary Bob Ainsworth said President Obama's lengthy deliberations over whether or not to send more troops had contributed to falling public support in Britain for the Afghan mission.
The British government later denied that Mr Ainsworth was blaming American delays over sending more troops to Afghanistan for any decline in public support.
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