A senior civil servant has told council chiefs the axe is hovering over nearly £50 million of funding for controversial transport plans in Bath.

Politicians meeting next week to discuss the Bus Rapid Transit scheme will do so with the warning that rejecting it will also kill off Government funding for the expansion of park and ride sites and improvements to key bus routes.

Councillors came within a hair's breadth of turning down the BRT at a chaotic meeting earlier this month and the ruling Conservative leadership is desperate to push its flagship scheme through this time.

The threat to the funding is spelled out in a new report to Bath and North East Somerset Council's development control committee and in a hard-hitting letter to authority chief executive John Everitt from Department for Transport official Julian Abel.

Mr Abel, head of regional and local major projects for the south west, said he was prepared to give the council until "mid-autumn" to secure planning permission for the BRT.

He says a recent discussion with council officers and their transport consultants "raised a number of serious concerns which must now question whether the scheme should continue to be prioritised for central funding."

The council is relying on £48.65 million of DfT cash for the Bath Transportation Package, which includes the BRT through Newbridge and the equally contentious Bathampton Meadows park and ride scheme.

Mr Abel's letter says his department was prepared to accept what he calls the "non-material" change of location to this site from the council's previous choice of Lambridge.

But he says the loss of the BRT "will fundamentally change" the package and that he would then recommend to ministers that the entire package would be taken off the list of projects to be funded.

The letter, sent on Monday, says: "Clearly the developments over the last week and proposed revisions place the future of the scheme at significant risk.  The loss of a scheme with such high potential would be disappointing and could represent a missed transport and funding opportunity in the long term for the Bath region."

Mr Abel says that if the BRT does get planning permission next Wednesday, he will need to see concrete plans to progress the package "to provide confidence to ministers that the authority is serious in taking this scheme forward."

The new report from planning officers to the meeting warns that rejecting the BRT - which would see a new dedicated bus route created along an old railway line - could even risk the viability of development at the city's Western Riverside.

The report mentions the recent meeting with civil servants.

It says: "They have stated that without the Bus Rapid Transit route, they would not be willing to continue to fund the package."

Opponents say the funding issues should not cloud councillors' judgements - and that the scheme has to be judged purely on its planning merits.

The report acknowledges: "The potential loss of funding is not in itself a material consideration to be taken into account in the determination of this application."

But it goes on: "The impact that failing to approve this element of the package would have on the deliverability of the rest of the package is a material consideration. "Members should therefore be mindful of the fact that, if this application does not get permission, none of the other elements of the Bath Transportation Package will take place."

The BRT route also includes a section through the largely derelict Western Riverside sector, where there are long-term plans for a new community of more than 2,000 homes.

The development is currently effectively on hold, with no start date because of the economic downturn, and the council has suggested that BRT buses would initially run along conventional roads between Windsor Bridge and the city centre.

But the report claims the BRT will be fundamental to the success of the Western Riverside once the recession eases.

It says the BRT would play a vital role in enabling restrictions on car ownership and use to work, and that without the scheme, fewer homes could be built.

"A Bath Western Riverside scheme with higher car provision would reduce the ability to provide housing numbers to support delivery of the Local Plan .... and weaken the council’s ability to secure private sector investment. Moreover the highway network would experience more congestion. Such a reconfigured scheme would be contrary to council policy and potentially open to third party challenge."

Objectors - who had called for next week's meeting to be postponed until after the summer holiday period - say the BRT route through Newbridge will destroy a much-loved green corridor without having any effect on pollution and congestion.

At a meeting on July 8, the council's development control committee voted against approving the authority's planning application to build the BRT and expand the Newbridge park and ride site.

But a follow-up vote to positively reject the application was tied and so councillors were controversially forced to vote to defer a formal decision.

Opponents and the Bath Heritage Watchdog pressure group claim the first vote was legal - and that the scheme should now be regarded as officially rejected, but the council's lawyers insist that the matter was deferred.

The meeting on Wednesday will be third time the committee has discussed the application.

In a statement, the anti-BRT Response2route campaign group said: "To many residents, it seems as if the current council leadership want the committee to keep on voting until they come up with their preferred answer."

The statement added: "It is not helpful that this protracted process will culminate at a committee meeting in the middle of the holiday season. However, residents will again be there to voice their strong objections and to urge the council to reject the plan and save their community."

It said councillors should reject the application on the grounds that it would adversely affect a large number of local residents through its visual impact, additional noise levels, increased pollution and loss of privacy and amenity, as well as its impact on trees and other wildlife habitats.

At the last meeting, the second vote ended in stalemate after committee member Cllr Brian Webber (Con, Abbey) abstained because, while opposed to the BRT, he is in favour of expanding Newbridge park and ride.

But Response2route spokeswoman Jo McCarron said: "This application is seriously flawed, and if any part of it is unacceptable on planning grounds then it should be refused as a whole."

The council has refused to split the application into two.

Meanwhile the Downstream South pressure group representing people living along Lower Bristol Road in East Twerton has repeated its calls for that road to be widened to accommodate a new bus lane.

Spokesman Denis Lovelace said several recent buildings had been constructed set back from the busy road to preserve space for such a bus lane, which he said would then make the BRT's Newbridge section unnecessary.

Next Wednesday's meeting is at the Guildhall at 2pm, but the BRT application is unlikely to be discussed until 5pm.