At least 150 Syrian dissidents have met publicly for the first time at a hotel in the capital, Damascus, to discuss the current crisis in their country.
The meeting's organiser, Louai Hussein, called for an end to the government's brutal crackdown on protesters and for a peaceful transition to democracy.
The event took place after government officials said they would not object.
Afterwards, the opposition was invited to joint talks to discuss the framework for a national dialogue conference.
The state news agency, Sana, said amendments to the constitution would be on the agenda at the conference on 10 July, including Article 8, which grants the Baath Party unique status as the "leader of state and society".
Participants would also examine proposed new laws on political parties, elections, local administration and the press, it added.
Sana said there was no alternative but to "open the door wide" to all Syrians, and to take part in building a "democratic, pluralistic society meeting the aspirations of the people".
The BBC's Lina Sinjab in Damascus says the government is making a show of looking for the middle ground to solve the crisis, but they are also seen to be playing for time.
Monday's meeting at the Semiramis hotel in Damascus was attended by several leading opposition figures, including Mr Hussein, Anwar al-Bunni and Michel Kilo, who have served time in prison for their political activities.
They began by singing the national anthem and holding a moment of silence to honour those killed in the revolt, which represents the most serious challenge to President Bashar al-Assad's rule since he succeeded his father in 2000.
In the opening address, Mr Hussein said it was an unprecedented event, and that no such conference had been held in Syria for decades.
"Those attending this meeting are not armed, [as they are not] terrorists or saboteurs," he said.
"We are meeting today... to put forward a vision about how to end tyranny and ensure a peaceful and secure transition to the hoped-for state: the state of freedom, democracy and equality."
In a final communique, the participants declared their support for the "popular uprising seeking a peaceful transition to a democratic, civil and pluralistic state", and called for an immediate end to the government crackdown and the withdrawal of the army from all towns and cities.
They also called for an independent committee to investigate the killings of civilians and security forces personnel, the release of all political prisoners, and the right to peaceful protests without official approval.
Human rights groups say more than 1,300 civilians have been killed and thousands arrested since pro-democracy protests began on 18 March. Several hundred soldiers and police are also said to have died.
The US state department said Monday's meeting was a "significant event", but the organisers were criticised by some opposition activists, who said it was a government ploy and that the attendees did not represent many of those involved in the revolt.
Notably absent were members of the Local Co-ordination Committees, which have sought to speak on behalf of young protesters. They refuse to begin dialogue while suppression continues and hundreds remain in detention.
"The Damascus Declaration coalition - this is the main opposition coalition in Syria - have actually come out against this meeting," Malik al-Abdeh, an editor of Barada TV, a Syrian opposition channel, told the BBC World Service.
"The regime is obviously happy for this conference to take place."
"In Syria, there are three or four opposition figures who spent time in jail, who are actually attending this meeting. But apart from that, all the other people I have seen on the list, they are not known to be opposition figures," he added.
"So this certainly is not an opposition conference, this is just a meeting of intellectuals all discussing the future of Syria under - I have to stress this - under the close watchful eye of the Syrian security."
Other activists have insisted that those taking part must stick to a basic demand - that the regime has to go, and make way for democracy.