The weapons suspension came as Boris Johnson also called on Ankara to end the offensive in a phone call with President Recep Erdogan, while the US said it would impose sanctions unless the assault was called off.
The European Union is expected to announce a coordinated response to the attacks after a meeting of its foreign affairs committee on Monday.
But Turkey showed no signs of backing down on Sunday as it continued to shell targets around border towns which are home to thousands of Kurds. Almost 200 people – many civilians – have been killed in the fighting. Some 130,000 refugees have been created, the UN has said, mostly those fleeing the bombarded towns of Ras al-Ain and Tel Abyad.
Ankara accuses the Kurds of being terrorists and says it wants to drive them out of a planned so-called “safe zone” reaching 30km into Syria.
It launched its invasion on Wednesday after US President Donald Trump withdrew American troops from the region – an unexpected move widely condemned by both domestic supporters and international allies alike.
Even the Turkish Republic in Northern Cyprus – a de facto state that is traditionally Turkey’s strongest supporter – called for peace and dialogue.
Concerns centre around the betrayal of the Kurds, one of West’s staunchest historical allies in the region, and the fact that the area is home to prisons containing thousands of Isis fighters.
Around 100 Isis-affiliated women and children escaped from a camp on Sunday, according to the Syrian Observatory for Human Rights.
The Kurdish-led Syrian Democratic Forces has said it cannot continue guarding these detainees if it also has to fight the Turkish army – meaning the release of countless terrorists into the already devastated region.
"Guarding Isis prisons is no longer a priority,” SDF spokesperson Redur Xelil said in a televised statement on Saturday evening. “Whoever cares about the secure detention of the prisoners, they are welcome to come and find a solution."
To add to the confusion, Isis declared on Saturday that it has already started regrouping and will launch a fresh campaign in Syria to avenge those members detained. It claimed responsibility for two deadly car bombs in the cities of Qamishli and Hassakeh which occurred on Friday.
In other developments, it has emerged Kurdish politician Hervin Khalaf was among nine civilians killed on a road in northern Syria by Turkish-backed forces. The secretary general of the Future Syria Party was ordered out of her car and executed, reports suggest.
A spokesman for the Turkish-backed rebel group the Syrian National Army denied carrying out the killings, saying it had not advanced that far, Reuters reported.
Separately on Saturday, thousands of people marched in a number of European cities, including Paris and Berlin, in protest against the Turkish assault.