Plans to close the outer circle of Regent’s Park to rat-running motor traffic are being “significantly watered down” to shutting just two gates – down from four – and to shorter periods, in only the morning and evening peak, it has been revealed.

Although still in discussion, plans for the road, which will form part of cycle superhighway 11 (CS11), have reportedly been under pressure from Westminster city council since they gained 60% approval in a public consultation in August 2016. Those close to discussions say weakened changes are now being blocked by the body that runs the park’s roads on the grounds they could be more dangerous than the status quo.

London’s former cycling commissioner, Andrew Gilligan, has declared CS11 dead under the two gate scenario, saying “The closure of the gates, and the removal of rat-running in the park, is the only thing which makes CS11 a meaningful route. But a nimby minority is vocally opposed to losing their rat-run.”

Westminster city council has been accused by the Crown Estates Paving commission (CEPC), which manages the park’s roads, of voicing opposition to the gate closures “at the last minute”, after years of talks with more than a dozen stakeholders. Gilligan says what is now on the table is closure of the North Gate and Park Square West, in the north-west and south-west of the park, respectively. The east side of the outer circle would still be open to rat-running motor traffic.

Gilligan says: “The hours of closure would be 7am to 9.30am and 4pm to 7pm, on Mondays to Fridays only; there would no longer be any closures of any gate at the weekends.” He adds there is also a new proposal to make Hanover Gate in the north-west corner entry-only during the rush hours.

A senior City Hall official told the Guardian the outer circle has almost three times as many collision injuries per kilometre than the central London average, with drivers recorded doing in excess of 80mph in its 30mph zone. Proposals to close four gates to the outer circle except between 11am and 3pm were intended to cut rat-running traffic. The two-gate proposal is reportedly designed to appease Westminster, but the CEPC says it will not support amended plans, which it says could be “more risky” for cyclists – a position Gilligan echoes. At present, the gates are open from 7am to midnight.

Max Jack, director of CEPC, which is also responsible for opening and closing park gates every day says Westminster city council “don’t want cycle proposals, they are not keen on cycle routes, and they aren’t very keen on gate closures”.

He said: “Westminster have a way of never being quite clear, you don’t know what they are supporting until the last minute. It was only when the consultation results came back that it became clear there was opposition about traffic displacement [on to Westminster’s roads] and that’s really what’s created the issue.”

CS11, due to run from Swiss Cottage to the West End, was proposed and consulted on under the former mayor, Boris Johnson, and Gilligan, his cycling commissioner, in 2016, but work on the route has not started.

The London Cycling Campaign’s Simon Munk says the reduced gate closure times will not tackle the problem of the afternoon school run, one of the major contributors to park traffic.

“Long term, through motor traffic has no business in any park, particularly this one,” says Munk. “It shouldn’t be acceptable that massive volumes of motor traffic, saving a minute or two on people’s journeys, are cutting through the park.”

“Every day, let alone every week and month that goes by, we risk further collisions.”

The two-gate closure plan has not been made public, and will reportedly not be consulted on again. CEPC, which is unrelated to the Crown Estate, says they “certainly won’t reduce the through traffic in the park very significantly”.

A senior City Hall source told the Guardian the discussions have delayed work on the CS11 route north of the park, as funnelling large numbers of cyclists on to the outer circle in its current state is considered a safety risk.

Jack says the CEPC does not want the scheme to fail, after “hundreds of hours” negotiating plans with stakeholders. “We were happy to support those [previously consulted] ideas because they had a strong chance of improving the park,” he said. “It’s a recreational space, you want to be safe cycling in a park. Whatever proposals happen, we take a park view: are they going to work for the park, are they going to improve the environment for all park users? That’s our frame of reference.”

Gilligan lays the blame at London mayor Sadiq Khan’s feet, saying Westminster was the “most lukewarm” main stakeholder during his discussions on CS11, but “if the mayor does really want something, and is prepared to press for it, you can overcome stakeholder opposition”.

The Royal Parks and Camden city council both say they support current proposals.

A spokesperson for Khan said: “Despite the positive consultation results there has to be agreement from all responsible authorities for the plans to be progressed, and we continue to work with all stakeholders to take these plans forward.”

A Westminster spokesperson said: “Westminster city council is one of a number of organisations consulted on this scheme and is not the decision making authority. The council was not supportive of the original proposal for the Regent’s Park gate closure.”