UN/Arab League envoy Kofi Annan says an international conference in Geneva has agreed that a transitional government should be set up in order to end the fighting in Syria.
This could include both members of the government and opposition.
The final communique said the transitional government should be formed on the basis of mutual consent.
It is for the people to come to a political agreement but time is running out, said Mr Annan on Saturday. We need rapid steps to reach agreement.
''The conflict must be resolved through peaceful dialogue and negotiations.
But US Secretary of State Hillary Clinton said President Bashar al-Assad could not remain in power.
She said they have stripped away the fiction that he and those with blood on their hands can stay in power.
However, Russian Foreign Minister Sergei Lavrov said there were no preconditions to the proposed transition that dictated who should or should not be in the transitional government.
Russia has blocked a provision in Mr Annan's plan that would have called for Mr Assad to step down to make way for a unity government.
The BBC reports Mr Annan also called for an immediate ceasefire and adherence to the UN's six-point peace plan.
He said humanitarian organisations and media should have access to Syria.
History will judge failure on Syria - Annan
Earlier, Mr Annan warned foreign ministers at the meeting that failure to agree on how to end the fighting in Syria there could ignite an international crisis.
Mr Annan told the meeting that world powers would be partly responsible for further deaths in Syria, if they fail to reach a deal.
He said history would judge harshly if there was no deal on ending the bloodshed.
History is a sombre judge and it will judge us all harshly if we prove incapable of taking the right path today, said Mr Annan.
Russia is said to be resisting proposals that could exclude President Bashar al-Assad from a transitional unity government.
British Foreign Secretary William Hague said President Assad and his close allies should not be allowed to take part in the interim Syrian administration being discussed at the talks.
Earlier, Mr Hague said reaching an agreement remained very difficult.
Russia has been hostile to any solution that would see Mr Assad forced out.
Attending the meeting were the foreign ministers of Britain, China, France, Kuwait, Qatar, Turkey, Russia and the United States, UN Secretary-General Ban Ki-moon, Arab League head Nabil Elaraby and EU foreign policy chief Catherine Ashton.
Not on the guest list were Iran and Saudi Arabia. Neither the Syrian government nor opposition were represented.
No outside solution - Assad
Meanwhile, Mr Assad said he would not accept any solution to his country's crisis imposed from outside.
He told Iranian television that it was an internal issue which had nothing to do with foreign countries.