George Osborne is the new editor of the London Evening Standard newspaper - 140 miles from his Cheshire constituency.
The Tatton MP maintains he 'intends to fulfil the promise' to serve his constituents.
Critics say taking on the role 'could not possibly be compatible with representing the interests' of people in Tatton.
Mr Osborne has made more than £600,000 outside Westminster since he was sacked as Chancellor.
He said: "I was elected by my constituents in Tatton to serve them and I intend to fulfil that promise.
“I remain passionate about the northern powerhouse and will continue to promote that cause.
"Right from the first speech I gave about the north of England, I’ve said that London needs a successful north and the north benefits from its links to a global city like London.
"It’s not a zero-sum game but quite the opposite.”
The London newspaper's owner Evgeny Lebedev described the Cheshire MP as 'London through and through'.
He added: "I am proud to have an editor of such substance, who reinforces The Standard's standing and influence in London.
"And whose political viewpoint – socially liberal and economically pragmatic – closely matches that of many of our readers.
"George is London through and through and I am confident he is the right person to build on the fantastic legacy of [departing editor] Sarah Sands."
His new job is still being considered by the watchdog that monitors the greasy 'revolving door' between politics and business.
But critics say the Advisory Committee on Business Appointments (Aboba) is 'futile' because it has no power to make MPs obey the rules.
A spokesman for Acoba told the Mirror : "We have received an application this week from him and the committee is considering it and taking advice from relevant departments."
Acoba has no power to base its decision on the fact George Osborne has so many jobs already - only the job on its own merits.
Labour MP for Ilford North in east London Wes Streeting said: “What does he think this will look like to his constituents in Tatton? How can he possibly think it is compatible with representing their interests?
“I'm not sure how many people in Cheshire read the London Evening Standard, but I would imagine this news will go down there like a cold bucket of sick.”
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