Police have been called to Jeremy Corbyn’s home where New Fathers 4 Justice campaigners are holding a protest on his roof.
It is being led by Bobby Smith, 34, and Martin Mathews, 49, who claim the Labour leader "was rude" to them.
A Met helicopter has been scrambled.
A police spokesman said they were called to Mr Corbyn's home in Islington at around 10.30am after receiving reports of the protest.
Father-of-two Bobby Smith, who has not seen his two daughters for five years, said: “I tried to talk to Jeremy in March and he was very rude to me.”
The protesters said they planned to stay "easily the rest of the day", adding they had plenty of food and water.
Asked whey they were on Mr Corbyn's roof, Mr Smith said: "He's in a position where he can hold the government to account.
"We'll stay here as long as we have to. We're willing to do anything for our children. Both of us would rather be home with our children right now."
A negotiator is talking to the men through a window.
Last year David Cameron complained that the group was being destroyed by the campaigners.
"It is falling apart because of Fathers for Justice clambering over my roof," he told the Evening Standard.
"The tiles are falling off, the window frames are rotten but I am happy there, we all are."
