Germany has issued entry bans for 18 Saudi citizens suspected of involvement in the killing of journalist Jamal Khashoggi in Riyadh’s Istanbul consulate, effectively banning them from the European Union’s passport-free Schengen zone.

Monday’s move represents a sharpening of the position of Germany, which last month imposed a ban on selling weapons to Saudi Arabia until the circumstances of Khashoggi's killing have been fully cleared up.

It suggests Berlin is prepared to use its influence as the EU’s largest country to push for a tougher European line, given the ban will effectively apply across the 26-country Schengen zone.

“We have coordinated closely with our French and British friends and decided, as Germany, to put an entry ban beside their names in the Schengen system database,” Foreign Ministry spokesman Christofer Burger told a regular news conference.

Any member of the Schengen area can unilaterally impose a binding entry ban on any individual it deems a security risk. France is part of the zone, Britain is not.

Nonetheless, imposing such a large number of bans at once in such a politically sensitive case is unusual.

Burger said the members of the 15-strong squad accused of carrying out the killing of the critic of Saudi policy, and a further three who are suspected of organising it, had been given entry bans. He declined to name the individuals.

Asked if Crown Prince Mohammed bin Salman, accused by United States intelligence of having ordered the killing, was among their number, Burger declined to comment.

Saudi prosecutors said last week that the crown prince, Saudi Arabia’s de facto ruler, knew nothing of the operation, in which Khashoggi’s body was dismembered, removed from the building and handed over to an unidentified “local cooperator”.

An Interior Ministry spokeswoman said the ban applied to holders of diplomatic passports, held by many members of the Saudi royal family.

A spokesman for the Economics Ministry said the ban on authorising weapons exports to Saudi Arabia remained in force. “There are no exports of weapons from Germany to Saudi Arabia at the moment,” he said.