Two main Syrian opposition groups have agreed on a political roadmap to end the ongoing civil war in Syria.

Officials from the National Coalition for Syrian Revolutionary and Opposition Forces (SNC) and the National Coordination Commission for Democratic Change (NCC) made the decision after a meeting in Brussels on Friday where they presented their roadmap to reporters.

The two opposition groups, who were at odds with each other, said that they agreed to "condemn the [Bashar al-Assad led Syrian] regime’s horrific targeting of unarmed civilians in all Syria’s cities, towns and villages using barrel bombs and missiles".

"The barrel bombs dropped daily on civilian population is being met [with] silence [by the international community]," president of the National Coalition for Syrian Revolutionary and Opposition Forces, Hadi al-Bahra, claimed.

Disagreements and accusations between the groups have caused divisions within the Syrian opposition. While the National Coalition for Syrian Revolutionary and Opposition Forces is exiled, the National Coordination Commission for Democratic Change has been tolerated by the Syrian government.

However, on Friday, both opposition groups said that they "reaffirm that the solution to the crisis in Syria can be achieved through a political process undertaken by Syrians themselves, under the auspices of the United Nations".

"The international community (is) talking about the opposition needing to unify rather than pressuring the regime," Hadi al-Bahra said.

"We are unified with regards to final demands; there is no country in the world with only one opposition," al-Bahra said.

More than 220,000 people have been in Syria’s civil war since March 2011, according to the U.N., prompting a refugee crisis that has seen Turkey become the world's largest refugee host.