British Foreign Secretary David Miliband said that military rule imposed by Pakistan's General Pervez Musharraf must be lifted within 10 days.
Asked if the British government backed a call by Commonwealth ministers on Monday that military rule must end by November 22, Miliband said: "Absolutely, the Commonwealth position was one that the UK played an important part in creating."
Commonwealth ministers are due to meet again on November 22 to discuss Pakistan's position within the group of 53 countries.
"That's why the 10 days has become important," Miliband told BBC radio.