US President Barack Obama is preparing to make a statement on the position of the embattled US forces chief in Afghanistan.

It follows a meeting at which Gen Stanley McChrystal was asked to explain his criticism of US officials.

US media reports say Mr Obama will announce that Gen McChrystal is to be replaced.

Mr Obama had said the statements in Rolling Stone magazine showed "poor judgement".

He is due to speak at 1330 Washington time (1730 GMT).

Gen McChrystal had been due to attend Wednesday's monthly meeting on Afghanistan and Pakistan and face some of those he - and his aides - criticised so publicly.

But it appears that he did not do so after meeting President Obama.

Afghan President Hamid Karzai has indicated that he does not want Gen McChrystal replaced.

'Enormous mistake'

Gen McChrystal arrived back in Washington in the early hours local time after being summoned from Afghanistan.

MARDELL'S AMERICA McChrystal's disappointment with the president was established at their first meeting. The general apparently felt Obama wasn't very interested Mark Mardell, BBC North America editor Read Mark's blog

Gen McChrystal quickly apologised for the magazine article, The Runaway General, written by Michael Hastings and due out on Friday, extending his "sincerest apology" and saying it showed a lack of integrity.

"It was a mistake reflecting poor judgement and should never have happened," he said.

US media reports said Gen McChrystal had submitted his resignation, but it was up to the president to decide whether to accept it. There has been no official comment on the reports.

White House spokesman Robert Gibbs said on Tuesday that the president was "angry" and that Gen McChrystal had made "an enormous mistake".

Mr Gibbs said "all options were on the table" regarding the fate of the general and wondered "what in the world was he thinking?"

Some experts suggest Mr Gibbs's harsh words were to make the president look tough and give him the option of keeping the general on after a warning.

However, some lawmakers have called for Gen McChrystal to quit.

The BBC's Kim Ghattas in Washington says President Obama has had to choose between continuity in leadership in Afghanistan at a crucial time, and a unified leadership which shows him respect as commander-in-chief.

At the White House meeting on Afghanistan and Pakistan, Gen McChrystal was due to face:

Joe Biden. Gen McChrystal had mocked the vice-president when asked a question about him. "Are you asking about Vice-President Biden? Who's that?"

Karl Eikenberry. Gen McChrystal said he felt "betrayed" by the US ambassador to Kabul during the long 2009 White House debate on troop requests for Afghanistan

James Jones. One of Gen McChrystal's aides says the national security adviser is a "clown... stuck in 1985"

Richard Holbrooke. Gen McChrystal says of an e-mail from the US special representative for Afghanistan and Pakistan: "Oh, not another e-mail from Holbrooke... I don't even want to open it"

The article also appeared to be critical of the president himself.

Referring to a key Oval Office meeting with Mr Obama a year ago, an aide of Gen McChrystal says it was "a 10-minute photo-op".

"Obama clearly didn't know anything about him, who he was... he didn't seem very engaged. The boss was pretty disappointed," the aide says.

In his first comments on the issue on Tuesday, President Obama said: "I think it's clear that the article in which he and his team appeared showed... poor judgement."

Reduced casualties

Duncan Boothby, a special assistant to Gen McChrystal who organised the Rolling Stone journalist's access to the commander, has resigned as a result of the article.

A spokesman for the Taliban said Gen McChrystal's recall was another sign of the start of the "political defeat" for US policies in Afghanistan.

But a spokesman for Afghanistan's President Hamid Karzai said on Wednesday that the Afghan leader believed replacing Gen McChrystal "would not be helpful" for peace and stability.

The spokesman, Waheed Omar, said: "We hope there is not a change of leadership of the international forces here in Afghanistan and that we continue to partner with Gen McChrystal."

The BBC's Quentin Sommerville in Afghanistan says there is a belief among Afghan officials that Gen McChrystal has brought real improvement on reducing civilian casualties caused by the coalition - they are down 44% so far this year.

There will be a special BBC programme on the implications of General McCrystal's meeting with President Obama on BBC World News TV and BBC World Service Radio at 1930 GMT.