The EU has stepped up sanctions on Syria by banning imports of its oil, as protests again broke out against the rule of President Bashar al-Assad.
Oil accounts for about 25% of Syria's income and EU member states take about 95% of its oil exports.
Dutch Foreign Minister Uri Rosenthal said the sanctions would "go straight to the heart of the regime".
Meanwhile, at least 14 people were reportedly killed as protesters again came out in force across the country.
Activists said seven had died in suburbs of the capital Damascus, four in the central city of Homs, and another three in Deir al-Zour in the east.
The United Nations says more than 2,200 people have been killed since pro-democracy demonstrations began in mid-March.
The UK Foreign Office said the European Union had agreed at official level to ban imports of Syrian oil into the EU to increase pressure on the Syrian regime over its crackdown against anti-government protest.
A spokesperson said it was hoped the agreement would be signed off by EU foreign ministers meeting in Poland on Friday and Saturday and come into immediate effect.
However, Italy has won a concession allowing it to fulfil existing contracts until 15 November.
The EU also added four more Syrian officials and three Syrian groups to its list of those affected by an EU travel ban and asset freeze.
Polish Foreign Minister Radoslaw Sikorski said: "President Assad is carrying out massacres in his own country."
In Paris on Thursday, US Secretary of State Hillary Clinton condemned Mr Assad's "brutality against unarmed citizens", adding: "The violence must stop and he needs to step aside."
The US has already banned the import of Syrian oil.
UK PM David Cameron has expressed frustration that a tough UN resolution on Syria has not yet been found.
He told the BBC on Friday: "We've been at the vanguard, arguing for a different approach to Syria. What [Mr Assad] is doing is appalling. He's had his chance to demonstrate he's serious about reform and he's blown it."
Russia, which has a veto on the Security Council, refuses to back a resolution imposing an arms embargo or asset freeze.
French Foreign Minister Alain Juppe meanwhile said his country would increase contact with Syrian opposition figures.
Last month, dissidents set up a "Transitional National Council" to co-ordinate the campaign against President Assad, following the example of the rebels in Libya. Burhan Ghalioun, a professor of political sociology at the University of Paris III, was appointed chairman.
Anti-government protests again broke out in various towns and cities after Friday prayers.
Activists reported that security forces were shooting at a number of demonstrations, including in the provinces of Idlib and Deraa, in suburbs of Damascus, in Aleppo and in the central city of Hama.
The London-based Syrian Observatory for Human Rights said Syrian forces had surrounded a number of mosques in protest hotspots, including Deraa and the eastern city of Deir al-Zour.
Another activist group, the Local Coordination Committees (LCC), said there had been a mass demonstration in Hama outside the home of Adnan Bakkour, to support the Hama attorney-general's decision to resign in protest at the killing of protesters.
The LCC reported another big protest in the northern city of Amuda, against Russian arms sales to Syria.
Syrian state television has denied most reports of protests, calling them "imaginary", although it said security forces had killed "two members of armed groups" in Talbisseh.
Access to Syria has been severely restricted for international journalists and it is rarely possible to verify accounts by witnesses and activists.
Activists on their Facebook page, Syrian Revolution 2011, had urged people out on to the streets under the slogan "death rather than humiliation", adding: "We are ready to die in the millions as martyrs."
The Syrian Observatory for Human Rights said seven people had been killed on Thursday, in Homs, Idlib and Deir al-Zour.