A multi-party group of four lawmakers made a trip to Syrian capital Damascus on Wednesday and met with senior ministers. Three of them -- excluding one from the ruling Socialist party -- met with Assad.
The unofficial trip, which was feted by the Syrian media, sparked an angry response from the French government, which cut diplomatic ties with Syria in 2012, supports the moderate opposition and seeks the removal of Assad from power.
"(They) have taken it upon themselves to meet with a dictator who is the cause of one of the worst civil wars of recent years," said President Francois Hollande during a visit to the Philippines.
According to the Syrian Observatory for Human Rights monitoring group, the conflict in Syria, which started as a pro-democracy uprising seeking Assad's ouster in March 2011 and morphed into a full-blown war, has left more than 200,000 people dead.
Prime Minister Manuel Valls, meanwhile, told TV station BFMTV that "for parliamentarians to go without warning to meet a butcher... I think it was a moral failing."
'ADOPT A BRAVER POLICY'
Jacques Myard, an MP from the opposition UMP party who was part of the trip, slammed France's "policy of blindness" towards Syria.
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"If Bashar falls, there will be chaos in the region," he told BFMTV on Thursday.
His comments reflect rising sentiment within Western countries that their governments should re-engage with Assad's regime to try and resolve the four-year bloody conflict and rein in the radical Islamic State (IS) group, which controls swathes of Syria.
They were echoed in Syria's Al-Watan daily, which is close to the government.
"This delegation is part of hundreds of elected representatives in France and in Europe opposed to the policies of their government on the Syrian crisis," it wrote.
It "is a message inviting European governments to adopt a braver policy by announcing a change in attitude towards our country and apologising for their attitude to the Syrian people."
On Wednesday, the former head of France's domestic intelligence service Bernard Squarcini said in a television interview that authorities would have to re-launch dialogue with Damascus.
"We cannot work on Daesh (IS) and against Daesh without going through Syria," he said.
But the French government remains firm in its political and military support for the moderate Syrian opposition, and wants to try and resolve the crisis through negotiations between members of the opposition and the Syrian regime -- but without Assad.
"The idea that we could find peace in Syria by trusting Bashar al-Assad and by thinking that he is the future of his country is an idea that I believe is wrong," Foreign Minister Laurent Fabius said Sunday.