It is understood Denis MacShane formally applied for the post of Crown Steward and Bailiff of the Chiltern Hundreds tonight - the traditional way of resigning from the Commons as there is no way for MPs to resign.
Chancellor George Osborne is expected to confirm his appointment tomorrow, at which point he will cease being an MP.
More top news
Singer reaches settlement with police following legal fight prompted by investigation conducted into him following sex assault allegations.
Manchester musicians Liam Gallagher, The Charlatans and Dave Haslam have pledged their support along with the Salford Red Devils.
Damon Smith from Newton Abbot was found guilty of planting a home-made bomb on the London Underground in October.