European Union countries summoned Iranian ambassadors on Friday to protest against the detention of Iranian staff of the British embassy in Tehran, but held off for now on tougher steps including visa bans. EU foreign ministers last week urged Iran to swiftly release Iranian employees of Britain's Tehran embassy and a Greek journalist detained as alleged instigators of street protests over disputed presidential election results. They warned of a “strong and collective response” against intimidation of diplomatic staff. An EU official said the 27 EU states agreed at a meeting in Brussels to take a gradual approach towards Tehran that could include visa bans and withdrawal of EU ambassadors from Iran, depending on how the situation evolved. “The first immediate action is to convey a strong message of protest against the detention of British embassy local staff and to demand their immediate release,” the official said. “Iranian ambassadors of EU member states have been summoned ... to convey this.” He said further steps would also be determined by the outcome of the meeting of the Group of Eight in Italy next week. A powerful Iranian cleric suggested on Friday that the detained local staff from the British embassy would be put on trial for their alleged role in the post-election unrest. In London, Britain's Foreign Office said it was “very concerned” about Ayatollah Ahmad Jannati's statement. The G8 deplored the violence stemming from Iran's police sweep against protesters after the disputed polls but kept the door open for Iran to enter into talks on its secretive nuclear program. British officials said nine local staff of its embassy in Tehran were initially detained and two were still being held. A spokeswoman for Swedish Foreign Minister Carl Bildt, whose country holds the EU presidency, said it would not be acceptable for Iran to file charges against the staff.