UN-Arab League envoy Kofi Annan said it would be hard to reach a deal to halt bloodshed in Syria but expressed optimism after meeting President Bashar al-Assad for a second day today.
"It's going to be tough. It's going to be difficult but we have to have hope," he told reporters in Damascus.
"I am optimistic for several reasons," Mr Annan said, citing a general desire for peace in Syria. "The situation is so bad and so dangerous that all of us cannot afford to fail."
The former head of the United Nations, who is from Ghana, said: "I have urged the president to heed the African proverb which says: 'You cannot turn the wind, so turn the sail'."
Mr Annan, speaking before departing for Qatar, said he had left "concrete proposals" with Assad for a way out of a conflict that has cost thousands of lives.
"You have to start by stopping the killings and the misery and the abuses that are going on today, and then give time (for a) political settlement," he said.
There was no immediate word from Syrian officials on the outcome of the talks, but Assad told Annan on Saturday that "terrorists" spreading chaos and instability were blocking any political solution, according to the state news agency SANA.
But it said the 46-year-old president had also told Annan he would help in "any honest effort to find a solution".
Syrians involved in a popular uprising against Assad say there can be no meaningful dialogue with a leader who has inflicted such violence and suffering on his own people.
"Him (Assad) stepping down is definitely a first condition of any discussion or negotiation," Bassma Kodmani of the opposition Syrian National Council told the BBC on Sunday.
The United Nations says Assad's forces have killed more than 7,500 people in a year-long crackdown on protesters and insurgents. Authorities say rebels have killed 2,000 soldiers.
Mr Annan's mission has coincided with a Syrian military offensive against opposition strongholds in the northwest.
Three soldiers and a civilian were killed in fighting in the village of Janoudiya in Idlib province on Sunday morning, according to the Syrian Observatory for Human Rights.
Its British-based director, Rami Abdulrahman, said Idlib city was quieter after Saturday's tank-led assault, suggesting outgunned rebels had withdrawn or decided not to confront the army, which has launched an offensive in the northwest after recapturing insurgent strongholds in the city of Homs last week.
The Observatory said 39 civilians, including 25 in Idlib province, were killed on Saturday, along with 39 rebels and 20 government soldiers, giving an overall death toll of 98.