Prime Minister Tony Blair has said he is opposed to the death penalty, but it was for the Iraqis to decide the fate of former president Saddam Hussein.
Saddam Hussein was sentenced on Sunday
"We're against the death penalty, whether it is Saddam or anybody else," he told reporters, but said there were "other and bigger issues" in Iraq.
An Iraqi court sentenced Saddam Hussein to death by hanging after he was found guilty of crimes against humanity.
Amnesty International has condemned the trial as flawed and unfair.
Mr Blair said Saddam's trial had given a "clear reminder of the barbaric regime" he had overseen.
But during repeated exchanges at his monthly news conference, the prime minister said he would not elaborate further on his position on the death penalty.
Asked if he thought the conviction of Saddam would be a "turning point" for Iraq, he replied: "I've become very cautious about claiming turning points."
Later his spokesman said the British government had "reminded" the Iraqi government of its opposition to the death penalty, but said it had to be recognised that Iraq was a "sovereign country" with its own courts system.
Liberal Democrat leader Sir Menzies Campbell has warned that executing Saddam could make him a martyr and said he should be imprisoned for life.
But Foreign Secretary Margaret Beckett told the BBC that only those "who had no quarrel with the regime all the way through" would think of Saddam Hussein in that way.
On the death penalty, Mrs Beckett said Britain did not approve of it but added: "This is the verdict of the Iraqi court and a matter for the government of Iraq."
Saddam's trial had been as "independent as it could be made" in difficult circumstances, she said
"His crimes had been committed in Iraq against the people of Iraq and they wanted to see him tried and judged on the evidence presented there.
"An alternative could have been an international court and that would not have been the same."
But Malcolm Smart, of Amnesty International, said the death penalty was "particularly abhorrent" because the trial had not been fair.
He cited the murder of three defence lawyers and the resignation of one judge who complained of government interference.
"Every individual, whatever the magnitude of the crimes against them, has the right to a fair trial and unfortunately that test has not been met this time," he said.
"I welcome the opposition to the death penalty, but this has been a flawed process".
Saddam was convicted over the killing of 148 people in the town of Dujail following an assassination attempt on him in 1982.
US President George W Bush called the verdict a "milestone" for Iraq but the EU urged Iraq not to execute him.
Shadow Foreign Secretary William Hague would not be drawn on whether he agreed with the death penalty decision, but congratulated the bravery of judges and witnesses "in the face of severe violence and intimidation."
Anas Altikriti, the British Muslim Initiative spokesman, said the "sad reality" was that the verdict could mean the Iraqi people would "never have their day in court".
"If he was indeed executed before the Iraqi people could find out what really happened over the last 30 or 40 years that would be another great tragedy," he said.
Scottish National Party leader Alex Salmond - a longstanding critic of the government's military campaign - said it was a "very understandable verdict given the terms of the court".
Dr Muhammad Abdul Bari, secretary general of the Muslim Council of Britain, said there had been concerns about whether Saddam would receive a fair trial in Iraq "given the sectarian tensions that are rife".