Marie Colvin's body en route to Damascus

The body of a British journalist killed in Syria was being taken to Damascus tonight after being handed over by the Syrian authorities, a charity said.

The International Committee of the Red Cross said the bodies of Sunday Times reporter Marie Colvin and French photographer Remi Ochlik, who were killed in a rocket attack in the besieged Baba Amr area of the city of Homs last week, were en route to the Syrian capital.

Earlier today, Prime Minister David Cameron vowed that Syrians involved in "butchering" their own people would face a "day of reckoning", adding that supporters of President Bashar Assad's "criminal regime" have blood on their hands.

A spokeswoman for the Foreign and Commonwealth Office (FCO) said: "We have been in touch with the Sunday Times and they are making arrangements for repatriation with the relevant authorities."

Speaking at an EU summit in Brussels at which Syria was high on the agenda, Mr Cameron described the situation in Homs as "a scene of medieval barbarity".

The Prime Minister urged China and Russia to end their support for the Syrian government, calling on them to "look hard at the suffering" in the city, where rebels have faced a bloody crackdown from Assad's forces.

"The Assad regime is butchering its own people. The history of Homs is being written in the blood of its citizens," said Mr Cameron.

"We will make sure, as we did in Serbia, that there is a day of reckoning for those responsible.

"So I have a clear message for those in authority in Syria: make a choice, turn your back on this criminal regime or face justice for the blood that is on your hands."

Immediate humanitarian access to the city - as demanded last night by the United Nations Security Council - was "the very least that must happen to bring immediate relief to those who are wounded or dying".

The International Committee of the Red Cross today said it was "unacceptable" that an aid convoy it has sent to Homs is being denied access to the Baba Amr district, which has borne the brunt of the 26-day siege.

ICRC president Jakob Kellenberger said: "It is unacceptable that people who have been in need of emergency assistance for weeks have still not received any help. We are staying in Homs tonight in the hope of entering Baba Amr in the very near future."

Russia and China, which vetoed an Arab-backed peace plan last month, are continuing to resist pressure to join global condemnation of human rights violations by the Assad regime.

However, they have backed a UN statement criticising the regime's refusal to allow UN humanitarian chief Baroness Amos access to Syria to inspect the aftermath of 11 months of violent repression.

"I say to the Russians and the Chinese: look hard at the suffering of Syria and think again about supporting this criminal regime," said Mr Cameron.

Russian prime minister Vladimir Putin denied that Moscow had any special relationship with Damascus and said the Syrians must choose who governs them.

"When Bashar al-Assad came to power he visited London and other European capitals first," he told The Times. "We don't have a special relationship with Syria.

"It is up to the Syrians to decide who should run their country. We need to make sure they stop killing each other."

Efforts to document the atrocities by Assad loyalists were backed by the European Council in its summit communique.

More than 7,500 civilians have been killed so far in the crackdown, the UN estimates, and its top human rights body voted to condemn Syria for "widespread and systematic violations" though without Russian or Chinese support.

Rebel forces last night made what they described as a "tactical retreat" from the Baba Amr area, which has become emblematic of the bitter struggle.

In a statement issued through the Syrian Embassy in London today, Assad's Ministry of Foreign Affairs expressed "sadness and sorrow at the tragedy that befell the American journalist Marie Colvin".

The statement said that the Syrian authorities had "exerted immense efforts to find out the circumstances under which Miss Colvin was killed and to take out the bodies in order to deliver them to the relevant authorities in their countries".

And it blamed insurgents for delaying the removal of the bodies and wounded journalists from Homs, and said that some of the reporters had themselves refused the offer of evacuation to Damascus by the Syrian Red Crescent and ICRC.

"Syria reiterates that it will deliver on all its commitments in relation to this humanitarian issue as long as the sovereignty of Syria and its territorial integrity are ensured," said the statement.

France has announced it is closing its embassy in Syria.

PA