A man has been arrested after British Labour leader Jeremy Corbyn was hit by an egg while on a visit in his north London constituency, according to British media reports.

A Labour Party source said Mr Corbyn was visiting the Finsbury Park mosque and Muslim welfare centre on Sunday and was unharmed.

The chief political correspondent for Britain’s Sky News, Jon Craig, said Mr Corbyn was unhurt by the egg, which was pressed down on his head rather than thrown.

The Metropolitan Police said a member of parliament had been struck by an egg on Sunday afternoon.

“A 41-year-old man was quickly detained by officers on scene and arrested on suspicion of assault. He is currently in custody at a north London police station,” it said.

British media reported the arrested man was a pro-Brexit campaigner.

The Independent newspaper said it understood Mr Corbyn was sitting chatting with community leaders when the attacker approached him from behind and hit him over the head with the egg.

The man was reportedly overheard to say “when you vote you get what you vote for”, the paper reported.

The alleged attacker is not thought to be a regular at the mosque, but had been waiting inside the building. After the incident, he was quickly surrounded by others in the room, and the police were called. 

Mr Corbyn was at Finsbury Park for Visit My Mosque Day, an annual campaign in which more than 250 mosques across Britain hold open days for people from all faiths.

He was presented with a bunch of red roses on his arrival, before meeting children involved in activities at the community centre.

On Thursday, Mr Corbyn said Labour would back a new referendum on Brexit after parliament defeated its alternative plan for leaving the European Union.

-with AAP