Anthony Douglas offered to meet the group and answer questions about Cafcass, signalling an end to the war of words between the organisation and the controversial pressure group. Cafcass is described on F4J's website as "the weakest link".
Relations between the two parties reached an all-time low after Napo, the trade union that represents family court staff, accused Fathers 4 Justice of waging a campaign of intimidation and violent threats against its employees. This claim is strenuously denied by the group.
However, Fathers 4 Justice has admitted to parking a double-decker bus outside the house of Dame Elizabeth Butler-Sloss, president of the family division of the High Court.
As a result, she still refuses to meet the group. She said: "As long as they throw condoms with purple powder and put a double-decker bus outside my house in the West Country, there is no point."
Fathers 4 Justice founder Matt O'Connor praised Douglas's approach. He said: "We welcome any chance to increase mutual understanding and ways of improving outcomes for children."
From next Monday, the group will also step up its campaign to target political parties in the run-up to the general election. Members will have a campaign bus and helicopter at their disposal.
On Monday, three Fathers 4 Justice campaigners, dressed as Batman, Robin and Captain America, climbed on to a ledge above Downing Street.
F4J will use 'guerrilla-style' action in its election campaign
The group will target high- profile MPs such as children's minister Margaret Hodge
A 'flying squad' has been set up, with a campaign bus and helicopter at its disposal
The group hopes to use bill-board adverts on busy routes such as the M4 into London.