PARIS - Thousands of people, some shouting "Erdogan terrorist", took to the streets of Paris and other European cities on Saturday in protest at the Turkish assault on Kurds in Syria.

Protesters marched under the Kurdish green, red and yellow flag waving placards.

Organizers said "more than 20,000 people" took part in the demonstration in Paris after Ankara stepped up its assault on Kurdish-held border towns in northeastern Syria on Saturday, defying mounting threats of international sanctions.

"Turkey is invading Rojava (the self-proclaimed Kurdish zone in northeast Syria) and Europe is watching," they shouted as they marched towards Chatelet in central Paris. Police in the capital estimated 4,000 people had taken part.

In France, a spokesman for one Kurdish group called for US and European Union sanctions against Turkey.

There were similar protests in other French cities including Marseille, Strasbourg -- the seat of the European parliament -- Bordeaux, Lille and Grenoble.

The Turkish offensive began on Wednesday after US President Donald Trump ordered American troops to pull back from the border.

Trump has faced a storm of criticism for abandoning a loyal ally in the US-led campaign against the Islamic State group.

Pro-Kurdish protests were also held across Germany with more than 10,000 participants in Cologne, according to news agency DPA.

Several hundred demonstrated in the Hungarian capital Budapest outside the Turkish and US embassies.

Scores of Kurds also marched through Cyprus's capital Nicosia, with one protester holding up a banner that read: "Do not be an accomplice to the genocide of the Kurdish nation."

Thousands marched in Vienna while in Athens, some 1,800 people according to police tried to march on the Turkish embassy. -AFP