LONDON — The senior British commander in Afghanistan says that a decisive military victory there is impossible and the Taliban may well be part of a long-term solution for the country.

The Sunday Times newspaper quotes Brig.-Gen. Mark Carleton-Smith as saying that the alliance is not going to win the war.

He says the issue now is about reducing the war to a manageable level of insurgency that's not a strategic threat and can be managed by the Afghan army.

General Carleton-Smith says the alliance may well leave Afghanistan while there is still a low but steady rural insurgency.

He also said a deal with the Taliban might be on the table.

The British commander says that if the Taliban is prepared to sit on the other side of the table and talk about a political settlement, that's the sort of progress that could conclude the insurgency.

Although Britain and its NATO allies are engaged in a fierce campaign against Taliban militants in Afghanistan, British officials have voiced interest in trying to talk the Taliban into laying down their arms and joining the government.

On Saturday, the British government denied a claim that the UK believes the military campaign in Afghanistan is doomed to failure, after a French newspaper reported that London's ambassador to Kabul had said foreign troops added to the country's woes.

On Wednesday, France's weekly Le Canard Enchaine published what it said was a leaked French diplomatic cable recounting talks between Britain's Ambassador Sherard Cowper-Coles and a French official.

The newspaper said the French cable reported that Cowper-Coles had said Afghanistan might best be "governed by an acceptable dictator" and that the cable quoted him as saying foreign troops were adding to the country's problems by helping shore up a failing government in Kabul.

Cowper-Coles was quoted as saying that "the American strategy is destined to fail" and that the presence of foreign troops in Afghanistan was "part of the problem, not the solution."

The prospect of a dictatorship "is the only realistic one and we must get public opinion ready to accept it," the report quotes the alleged cable as saying.

The newspaper, a weekly publication known for its investigative stories, published excerpts of the cable, including a passage that quoted the British ambassador as criticizing both U.S. presidential candidates over pledges to send more U.S. troops to Afghanistan.

"It is the American presidential candidates who must be dissuaded from getting further bogged down in Afghanistan," an extract of the cable published by the newspaper quoted Cowper-Coles as saying.

The newspaper said it had obtained a copy of the two-page cable, which it reported was sent from Kabul to Paris on Sept. 2.

It said the cable was written by France's deputy ambassador in Afghanistan, Jean-Francois Fitou, following his meeting with Cowper-Coles.

It said the cable was sent to French President Nicolas Sarkozy and Foreign Minister Bernard Kouchner.

French Foreign Ministry spokesman Eric Chevallier declined Saturday to comment on the alleged cable, refusing to either confirm or deny its existence.

However, Chevallier said the content of the alleged cable, as reported by the media, "doesn't correspond at all with what we hear from our British counterparts in our discussions on Afghanistan."

Britain's Foreign Office said Cowper-Coles had held a meeting with a French counterpart, but insisted that the reported comments did not reflect the government's views.

Writing on his Web site Friday, Britain's Foreign Secretary David Miliband described the report as "garbled," and insisted that Britain does not support a move toward a Kabul dictatorship.

"The future of Afghanistan is not about appointed dictators or foreign occupation; it is about building Afghan capabilities with the confidence of the Afghan people," Miliband wrote.

A Foreign Office official, who demanded anonymity to discuss the purported leaked cable, said the claim that Cowper-Coles advocated a dictatorship in Afghanistan was "utter nonsense."

The official said the comments attributed to the ambassador were likely to have been a distortion, or exaggeration, of what he had actually said in the meeting.