While the rest of the world is focussed on Ukraine, as Russia's war crimes multiply there, Erdogan is "planning to launch an umpteenth bloody offensive against the Kurds in northern Syria," the parliamentarians said in a statement published by the JDD title.
The Turkish president "is taking advantage" of Turkey's pivotal status, as a NATO member on good terms with both Moscow and Kyiv, "to obtain a blank cheque from the Atlantic Alliance in order to intensify his attacks in northern Syria", according to the statement initiated by Communist senator Laurence Cohen.
"Western countries must no longer look the other way", said the elected representatives, parliamentary deputies and upper house senators mostly from leftist and ecologist parties.
They were joined by some from the rightwing Republicans (LR) and President Emmanuel Macron's ruling party.
They called on the West "to guarantee the protection of Kurdish activists and associations present on European soil".
The signatories urged France to refer the matter to the UN Security Council "to declare a no-fly zone in northern Syria and place the Syrian Kurds under international protection".
They also called for the Autonomous Administration of North and East Syria (AANES) to "be granted international recognition".
Erdogan is threatening to launch a new military offensive against Kurdish-controlled areas of northern Syria, where he wants to establish a buffer zone 30 kilometres (20 miles) deep.
Turkey has launched a string of offensives in Syria in the past six years, most recently in 2019 when it conducted a broad air and ground assault against Kurdish militias after former US president Donald Trump withdrew American troops.
Erdogan has urged Russia and Iran to back his efforts, saying at a three-way summit last week that "we will continue our fight against terrorist organisations".