Conservative Party chairman Grant Shapps has called on Ed Miliband to "come clean and publish Labour’s report into the Falkirk selection in full."
Mr Shapps added, "It’s clearer than ever that [Unite chief] Len McCluskey is calling the shots in the Labour Party."
More top news
Police found one child chained to the ground, another tied to a door with a dog lead, while six others were also rescued.
Wintry scenes across the UK this late in April have not been seen since the mid-1980s.
The Labour leader will also announce an inquiry into anti-semitism and other forms of racism to be chaired by Shami Chakrabarti.