United States President-elect Barack Obama [Images] plans to issue an executive order, within his first week in office, to close down the infamous American detention centre at Guantanamo Bay, a media report said on Tuesday. The order, however, would not immediately close the prison, the Wall Street Journal said, citing two people with knowledge of the plan.

It is the first step in what is expected to be a long process of determining what to do with the approximately 250 suspects and potential witnesses in the 'war on terror' who are held at Guantanamo, the paper said, adding that Obama is expected to issue several executive orders in his opening days in office.

Meanwhile, the New York Times quoted experts as saying that it is likely to take many months, perhaps as long as a year, to empty the prison that has drawn international criticism since it received its first prisoners seven years ago.

One transition official said the new administration expected that it would take several months to transfer some of the remaining prisoners to other countries, decide how to try suspects and deal with the many other legal challenges posed by closing the camp.

An official familiar with the plans was quoted as saying that an order regarding interrogation methods is also planned. Obama, who while electioneering had pledged to close down Guantanamo Bay, had acknowledged over the weekend that the process will take time.

The Guantanamo prisoners include the so-called 'high-value detainees,' the US officials still consider dangerous. Among them is Khalid Sheikh Mohammed, the alleged al Qaeda mastermind of the 9/11 terrorist plot, the New York Times noted.

Quoting people familiar with Obama's plans, the paper said the executive order will direct officials to examine each detainee's case to determine who can be released and find a place to send those who must remain held.

"It is more difficult than I think a lot of people realise," Obama told ABC's This Week." "I think it's going to take some time."

"But I don't want to be ambiguous about this. We are going to close Guantanamo and we are going to make sure that the procedures we set up are ones that abide by our Constitution," he added.