Allies of Mr Burnham, who will walk through the doors of No 10 in just over a week's time, are understood to be studying a raft of proposals, which would hammer the rich.

UK families could face significantly larger tax bills under a Burnham premiership, as speculation over his potential changes

Experts have warned middle-class families, who live in relatively modest homes and not 'mansions' as the term would suggest, would be dragged into the tax.

Allies of Mr Burnham, who will walk through the doors of No 10 in just over a week's time, are understood to be studying a raft of proposals, which would hammer the rich.