Leyton and Wanstead MP John Cryer will be the main speaker at a meeting next week held by campaigners against the government's 'bedroom tax'.
The Labour backbencher has claimed 733 households in his constituency will lose an average of £728 from the reforms.
Under the changes, those living claiming housing benefit are having some of their payments cut if they are judged to have "spare" rooms.
The government says the changes will help reduce the welfare bill and cut the number of under-occupied homes, but critics say the measures will push vulnerable people into greater poverty.
The meeting takes place at the Epicentre in West Street, Leytonstone, on Tuesday at 7.30pm.
Other speakers include Pilgrim Tucker from union Unite and Rob Murthwaite of the Disabled People Against Cuts group.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here