Hundreds of people have demonstrated against President Bashar al-Assad outside the Syrian embassy in London.
They called for President Assad and Libya’s embattled leader Colonel Gaddafi to step down.
On Friday, Foreign Secretary William Hague welcomed an EU move to impose sanctions on Syrian government officials.
Human rights activists say more than 580 people have been killed in the Syrian uprising since mid-March.
Syrian officials have said far fewer people had died and claim most of those had been soldiers and policemen killed by “armed terrorist groups”.
Protesters in the UK came from as far afield as Leeds, Bradford and Luton and called for an end to violence in Syria, Libya and Yemen.
One woman protester, who said she fled Syria 35 years ago, said it would be very hard to oust President Assad.
The woman, who did not want to give her name for fear of her relatives in Syria being targeted, said: “He (Assad) is ruthless and vain and in a strong position.
“Everyone is terrified of the regime in Syria, you cannot talk about politics, you cannot talk about anything. The walls have ears.
“Sadly I don’t think anything will change there until a lot more blood is shed.
She said she wanted the British government to do more to undermine the Assad regime.