Transport for London is trying to formally appeal the High Court’s decision to block CS11 – the controversial cycle route that would have ripped up the Swiss Cottage gyratory.

This latest twist in the cycle superhighway legal battle came as an application was lodged with the Court of Appeal on October 11. Westminster City Council and Camden Council have both been notified.

In September, the judge presiding over the judicial review, Sir Ross Cranston, denied TfL permission to appeal the ruling through the High Court, and told it to pay £50,000 in legal fees. TfL said his ruling was “procedural” and insisted it could still apply to the Court of Appeal.

Sir Ross’s decision stopped work on the gyratory in its tracks, after an injunction had postponed its planned July start-date at the last minute.

It is believed that, despite the judge’s ruling, TfL still hasn’t provided Westminster with the traffic modelling data at the centre of the legal battle.

The Court of Appeal now has to decide whether or not to actually grant TfL leave to appeal, which would see a court date set.

TfL’s application says: “The learned judge erred in failing to appreciate the defendant could and had rationally concluded that the claimant would come to allow a cycle superhighway to be constructed within its area.”

It also says the ruling undermines the London mayor’s ability to secure transport facilities in London.

Jessica Learmond-Criqui, whose Save Swiss Cottage campaign was named as an interested party in the judicial review, said: “TfL have not taken on board what the judge said, and instead of working with Westminster City Council in finding a solution and supplying the modelling data, are trying to muscle their way through instead.”

Westminster City Council’s environment chief Cllr Tim Mitchell said: “TfL’s appeal is extremely disappointing news.

“We’ve called and written to TfL asking them to get around a table and work with us on a solution to CS11 but they are clearly not interested.

“TfL has already lost in court once. We want to do the best thing by residents and cyclists, and that means accepting the judge’s verdict and working together on a way forward, but instead TfL are trying to cut corners with another costly court battle.

“We don’t know what they’ve got to hide. We say to them: share the additional modelling you promised and let’s get on with planning CS11.”

A TfL spokesperson said: “Following the judge’s ruling we are urgently exploring all options available to us to reduce danger around the Swiss Cottage gyratory, which includes seeking permission to appeal the decision.

“This junction is one of London’s most dangerous and the scheme would help protect all road users, particularly those walking and cycling, while significantly improving the area for residents, visitors and businesses.”