London transport bosses have been accused of 'trying to silence' farmers after they banned their anti-inheritance tax adverts from the Tube over their 'politically controversial' anti-Government message.

The National Farmers' Union (NFU) planned to spend £40,000 on posters around Westminster station with its 'Stop The Family Farm Tax' campaign slogan to attract MPs' attention to the row when they return to Parliament on January 6.

But top brass at Transport for London (TfL), which reports to the capital's Labour mayor Sadiq Khan, say the adverts do not comply with their rules and need to be watered down to remove any attacks on the Government.

Victoria Atkins, Tory rural affairs spokesman, said: 'Labour know they're in the wrong.'