Russia said on Tuesday it would not allow clashes between Turkey and Syria as Ankara presses a military operation against Kurdish forces.

“This would simply be unacceptable,” Moscow’s special envoy on Syria, Alexander Lavrentyev, was quoted as saying by Russian news agencies. “And therefore we will not allow it, of course.”

Meanwhile, Britain said it was suspending military exports to Turkey following its incursion into northeastern Syria, as it carries out a review of arms sales to its Nato ally.

“We will keep our defence exports to Turkey under very careful and continual review,” Foreign Secretary Dominic Raab said in a statement to parliament.

“No further export licences to Turkey for items which might be used in military operations in Syria will be granted while we conduct that review.”

Ankara’s assault against Kurdish forces launched last week has prompted a chorus of international condemnation. Raab said it had “seriously undermined the security and stability of the region.”

“This is not the action we expected from an ally, it is reckless, counterproductive, it plays straight into the hands of Russia and the Assad regime,” he told lawmakers.

Nato Secretary General Jens Stoltenberg discussed the volatile situation with British Prime Minister Boris Johnson in Downing Street on Tuesday.

Speaking after the meeting, Stoltenberg said the arms suspensions showed “many Nato allies are very critical and are condemning the military operation in northern Syria.”

Britain’s halting of military sales to Turkey follows similar moves by key European and Nato allies, including Germany — one of Ankara’s main arms suppliers — and France.

US President Donald Trump warned on Monday that Turkey faces imminent sanctions over its actions but also signalled that Washington would avoid any armed conflict with Ankara.

Turkey’s President Recep Tayyip Erdogan has said threats of sanctions and arms embargoes by Western powers will not stop the military offensive.

Also during the day, relatives of French militants and their families held in Syria said the Turkish offensive and the ensuing advance of Syrian President Bashar Al Assad’s forces have added to the urgency of bringing them home.

Hundreds of radicalised French men and women travelled to Syria to join Daesh at the peak of the group’s dominance, sometimes taking their children with them.

Most were captured when the extremist group was militarily defeated by Kurdish-led forces, backed by an international coalition.

Around 12,000 Daesh fighters, including 2,500-3,000 foreigners, are being held in Kurdish prisons with a further 12,000 foreigners — 8,000 children and 4,000 women — detained in camps in northeast Syria, according to Kurdish sources.

Turkey is now taking control of parts of the area as it presses its operation against Syrian Kurdish fighters. At the same time Assad’s forces are advancing from the south to contain the Turkish offensive.

Referring to the fate of the militants, Asma, a French woman whose brother is being held in a Syrian Kurdish prison, asked: “If Assad retakes the prisons, what is going to be their future?”

“Either they will be tortured or they will be used for bargaining or they are going to escape,” said Asma, who like other sources interviewed by reporters for this story asked for her name to be changed.

The worst scenario, she said, would see them end up back in the hands of Daesh, allowing “a terrorist organisation to be rebuilt.”

The fate of the foreign fighters and their relatives has divided the Turks and their Syrian Kurdish foes, with both sides accusing each other of freeing prisoners in a bid to sow chaos.

“I’m hoping for just one thing — that the state repatriates them,” said another woman Estelle, who believes a male relative is being held in Derik prison in Syria.

“If Assad’s regime retakes the prisons I do not know if it will be possible to go and find him,” she said.

The issue of the repatriation of French militants and their families has been a longstanding controversy in France, with families taking legal action in a bid to force the state to allow them home.

France has said it will consider requests for their return on a case-by-case basis only and has so far only taken back a handful of children.

Agencies