RIYADH (Reuters) - Syria now has a good opportunity to reach a political solution to its devastating eight-year war as ceasefires have brought calm to many areas of the country, Syria’s chief opposition negotiator said on Saturday.

“I think now that we have an opportunity, because nearly in Syria we have a ceasefire now, in the northeast of Syria and the north of Syria, and the efforts of fighting terrorism has achieved good results,” Nasr Hariri told Reuters in an interview in the Saudi Arabian capital Riyadh, where he is based.

Hariri, the opposition’s chief negotiator in U.N. peace talks, met with the newly appointed United Nations Special Envoy to Syria Geir Pedersen on Friday.

“Now it is time to invest all of these developments: the ceasefire, fighting terrorism, the belief of the majority of the Syrian people that the only solution to the Syrian crisis is the political solution,” Hariri added.

In December, Russia, Iran and Turkey - supporters of the main sides in Syria’s complex civil war - failed to agree on the makeup of a U.N.-sponsored Syrian Constitutional Committee but called for it to convene early next year to kick off a viable peace process.

Syrian President Bashar al-Assad, whose forces have reclaimed most of Syria with Russian and Iranian support apart from the northern province of Idlib, has clung to power throughout the conflict and is widely seen as being loath to yield power after it ends.

Arab states, including some that once backed rebels against Assad, are seeking to reconcile with him after decisive gains by his forces in the war, aiming to expand their influence in Syria at the expense of non-Arab Turkey and Iran.

“All the countries... Turkey, to some extent Russia and the Arab countries believe ... that without a political solution, the normalization with the (Assad) regime would be impossible,” Hariri said.