The British Government is funding a number of organisations to compile details of human-rights abuses by the Syrian regime, which could be used as evidence in future war-crimes trials.
Britain is also pressing to add to a list of Syrian officials who will be subjected to the full rigours of European Union sanctions. These names could be used to track down and target those culpable of tortures and killings, diplomatic sources said.
A senior Western diplomatic source said: "Britain is funding some organisations to document abuses. We have also got designated names for EU sanctions. These are travel bans and assets freezes at the moment, but they may be something else in the future."
With diplomatic options narrowing after Russia and China vetoed an Arab League-sponsored UN Security Council resolution asking for a transition of power, Britain will join the "Friends of Syria", which will pursue punitive measures against the Syrian regime. The group will comprise Middle Eastern and Western European states and the US. But the UK would like to see a wider field with countries like Japan and India invited to join.
France and Turkey have offered to hold the first meeting of the Group with Washington pressing for it to take place as early as next week.