Ministerial driver on day Thatcher left Downing Street

Some political secrets are shared with ministerial drivers, who hear the Westminster gossip and moments of history ahead of journalists and even politicians from the same party.

Former government driver Denis Oliver moved from the front seat to be a passenger around Westminster as he recalled how he knew before another minister that Harold Wilson was set to resign.

And he was also in the driving seat the day Margaret Thatcher stepped out of Downing Street for the last time, which he described as a "most amazing journey".

Giles Dilnot reports on the "government drivers' network".

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