LIB DEM ex-minister Norman Baker moaned yesterday that he quit his Home Office role because Tory colleagues had “soured things” and put “obstacles in the way.”

The pro-drugs reform Lewes MP, belittled by Conservatives as a conspiracy theorist, walked out of Home Secretary Theresa May’s department on Monday night complaining of the “constant battle” he faced over policy.

Chancellor George Osborne mocked punchbag Mr Baker from the dispatch box yesterday in a show of public schoolboy contempt for his theoretical ally.

Launching a typically pompous quip at Labour shadow chancellor Ed Balls’s economic “fantasies,” Mr Osborne said: “There’s now a vacancy — because the honourable member for Lewes has resigned — for a conspiracy theorist at the Home Office. He should apply.”

Mr Baker apparently reached breaking point last week when a report concluding that “wars on drugs” don’t work was publicly slapped down by the Conservative front bench.

He complained that those within Ms May’s department had no interest in the Lib Dems’ evidence-based policy.

“I’m afraid that the Home Secretary, who I think is a formidable woman and a very competent Home Secretary, has one great drawback, which is that she regards this as a Conservative department in a Conservative government and it’s not,” added Mr Baker.

“Her special advisers, in particular, were scrutinising what I was doing and they tried to minimise my room for manoeuvre.”

His job will now go to Lib Dem Hornsey & Wood Green MP Lynne Featherstone.