Officials in charge of the High Speed 2 rail project withdrew a “grossly misleading” advert following a complaint to the Advertising Standards Authority (ASA) by a Camden campaigner.

Fran Heron, who lives on the Ampthill Estate near Euston, raised 19 issues with the ASA over an online promotional video, which proclaimed “the new North-South HS2 line is like a bypass easing the strain on the clogged arteries of the system”.

In her strongly worded letter, Ms Heron wrote: “The advert has been designed specifically to convince a sceptical public of the merits of the scheme using tax payers money to do so and, as such, it should be scrupulously accurate.”

She concluded: “I believe the accompanying commentary is biased, contains factual errors, makes assumptions that are not proven [and] uses disputed figures and statistics.”

The ASA upheld 15 of the issues raised, including claims that HS2 would stimulate growth around the UK, that it would deliver £2 for every £1 spent, and that the project would lead to homes being created.

HS2 Ltd, the state-owned company responsible for delivering the high speed rail link, agreed to remove the video from its website, avoiding an ASA investigation.

Stop HS2 campaign manager Joe Rukin said: “It is clear that HS2 Ltd has decided to withdraw a grossly misleading advert rather than have the ASA rule that they had produced a grossly misleading advert.”

But the Department for Transport, which commissioned the video, insisted it had intended to take it down regardless of the complaint because the music rights were soon to run out.

“We stand by the information provided in the footage,” a spokesman said. “The case for HS2 is clear – it is a vital part of our long-term economic plan.”