Cyclists use the new Dunsmuir bike lane on Tuesday morning. (Mark Forsythe/CBC)

Vancouver Coun. Suzanne Anton is backpedalling on her support for the Hornby Street bike lane after learning preparations to start construction were underway even before the council vote.

The vote to go ahead with the controversial separated bike line through downtown Vancouver received unanimous support after a lengthy public hearing on Tuesday night.

But Anton said she now wants to rescind her support for the project after learning city engineers had the project ready to go before the public hearing and crews began construction just hours after the vote.

Anton says she was persuaded over the course of discussions Tuesday that the Hornby route was the best option from an engineering standpoint, but once she saw how quickly work began on the lane, she realized the meeting was just a formality.

"To me the process was a political sham and I don't want to be part of that. The crews were on the street a few hours later. There was no doubt that it was a done deal," she said.

The city's director of transportation Jerry Dobrovolny acknowledged that preparation for the $3.2 million project was done in advance, but said the lane was not a done deal until city council formally approved it on Tuesday.

"Anytime we have a major construction project like this, the work starts much earlier, but the final decision is always with council and it could have gone one of many ways," said Dobrovolny.

The lane is expected to take 10 weeks to complete and remain in place for at least six months.