The officer, who was on guard, suffered minor injuries when unknown assailants threw a hand grenade outside the embassy, located opposite Parliament on a major avenue in the centre of the Greek capital, early on Thursday.

Police shut down the area to vehicles and pedestrians, while anti-terrorism forensics experts combed the scene for evidence.

Police said the attack was apparently carried out by two people on a motorbike, and a bike matching the description was later found in a central Athens neighbourhood and was being examined.

Greece has a history of domestic militants who periodically carry out bomb or shooting attacks against authorities, diplomatic locations or businesses.