The Liberal Democrat president will vote against the bedroom tax in tonight’s vote.
Sources close to Tim Farron said he will vote for Labour’s motion to abolish the controversial policy in a House of Commons vote tonight.
Mr Farron feels duty bound to vote against the policy, after grassroots members passed a virtually uncontested motion condemning it at the party conference in September.
As president Mr Farron is the voice of members, and wants to ensure their voices are heard, a source said.
Former leader Charles Kennedy and West Cornwall MP Andrew George are also understood to be planning to vote against the government.
Four other Liberal Democrat MPs- Greg Mulholland, Ian Swales, Adrian Sanders and Roger Williams- have also tabled an early day motion branding the policy ‘a mistake.’