(CNN) -- The diplomatic fallout over this week's attack on Britain's Embassy in Iran deepened Saturday as France temporarily reduced its embassy staff and Italy's ambassador Iran was summoned home.
A French Foreign Ministry spokesman said the reduction is for "security reasons."
"Some of their diplomatic staff and their families will leave Iran and return to France," said the spokesman, who did not want to be named because he is not authorized to speak to the media. He couldn't say how many people are leaving, when they are departing and for how long.
Italian Foreign Minister Giulio Terzi received Italy's envoy to Tehran in Rome after he was recalled for consultations, said Italian Foreign Affairs spokesman Maurizio Massari. The ambassador, Alberto Bradanini, will not return to Tehran until Italy has received assurances on the protection of its diplomatic mission.
"There has been no decision to close the embassy," Massari told CNN. "We have received some assurances from the Iranian ambassador to Rome, but we would like to get more full guarantees of the security and protection of our diplomatic mission according to international law before sending our ambassador back to Tehran."
The spokesman went on to say that Italian officials are "staying in close contact with our European partners and allies."
Meanwhile, 25 Iranian diplomats and embassy employees arrived in Tehran Saturday morning after Iran was ordered to close its embassy in London, according to the Islamic Republic News Agency, the country's official news agency.
The group was greeted by a crowd of university students at Tehran's Mehrabad airport, the agency reported.
Relations between the nations have been strained in recent days after the United Kingdom levied new sanctions against Iran.
The sanctions were announced in late November and mandated that British credit and financial institutions end their business relationships and transactions with all Iranian banks, their branches and subsidiaries. The move came after an International Atomic Energy Agency report highlighted new concerns about Iran's allege moves towards producing a nuclear weapon.
The sanctions prompted protests in Iran and the attack on the British embassy in Tehran on Tuesday.
British authorities responded on Wednesday, by closing Iran's embassy in London and ordering Iranian diplomats to leave the country.
One senior ayatollah said protesters "must not act above the law."
IRNA quoted Ayatollah Naser Makarem-Shirazi as saying that "sometimes some of our dear young people become emotional and do things that gives an excuse to to our enemies and we have to pay a great price."
He urged young people not to "take any action without the permission of the Supreme Leader, Ayatollah Seyed Ali Khamenei."
CNN's Elizabeth Joseph contributed to this report.