United Nations Secretary-General Ban Ki-moon has condemned authorities in Syria for using tanks and live ammunition against anti-government protesters.
Speaking after a Security Council meeting, Mr Ban says the Syrian authorities have an obligation to respect human rights.
Troops have been deployed in a suburb in Damascus, while fighting has continued in the southern town of Deraa.
Britain and other European states are pressing the Security Council to adopt a statement that would condemn the violence against protesters and urge restraint, the BBC reports.
Western nations want the council also to send a strong diplomatic signal to the Syrian government that its crackdown is unacceptable.
Anything more than that, such as sanctions, is unlikely at this stage. China and Russia do not like the UN interfering in what they see as internal disputes and they are especially cautious following military intervention in Libya, the BBC reports.
Another member of the Security Council, Lebanon, is also uneasy about condemning the government, as Syrian influence is very strong in the country.
Syria 'at a fork in the road'
Meanwhile, Britain, France and Italy have called on Syria to stop its violent oppression of pro-reform demonstrators.
British Foreign Secretary William Hague says his country will work with its European partners to impose sanctions on Syria if Damascus continues its repression.
"Syria is now at a fork in the road," Mr Hague says. "Its government can still choose to bring about the radical reform which alone can provide peace and stability in Syria for the long term, and we urge it do so. Or it can choose ever more violent repression."
On Tuesday, the United States said it was considering targeted sanctions against the Syrian government.
More gunfire reported in Deraa
More gunfire has been reported in the Deraa, a day after troops backed by tanks moved in to stop further anti-government protests.
The official Syrian news agency says a number of soldiers have been killed.
With foreign journalists banned from Syria there is no independent confirmation of what is happening on the ground, but reports suggest that as many as two dozen people may have died in Deraa on Tuesday.