The site of the Albion's proposed home at Falmer could be inside the borders of the new South Downs national park.

Countryside chiefs meeting tomorrow will be told land earmarked for the stadium should be included in the park, a move that could jeopardise the project.

The stadium site is already protected inside the Sussex Downs area of outstanding natural beauty (AONB) but including it in the park will mean conservation rules are applied more vigorously.

National planning guidelines say major developments should not be permitted in AONBs or national parks unless there was overriding national interest.

Opponents of the stadium would have more leverage to defeat the scheme if it was inside a national park.

The draft boundaries, which may not be approved by the agency tomorrow, will be investigated for three months from November.

Brighton and Hove City Council has provisionally included the stadium in its local plan, which has yet to go to a public inquiry.

The Countryside Agency's board will be told the site should not be included because proposals to build the stadium were not in any existing plans.

Council leader Ken Bodfish said the stadium could still go ahead if it made it into the local plan.

He said: "If it was in the local plan, even if it was designated as a national park, my guess is you could go ahead with it.

"It does not rule out a stadium at Village Way North. Village Way South is a different kettle of fish."

Plans to build at Falmer were thrown into turmoil in June when the University of Brighton withdrew its support for the project on the site at Village Way North.

The Albion responded by saying it wanted to build 200 metres away at Village Way South, angering environmentalists who claim the stadium would be higher up and more visible.

Mr Bodfish raised further doubts about the project in July when he said the club should reconsider building at Waterhall, also likely to be in the national park.

The council subsequently agreed to continue supporting Village Way North.

Robin Crane, of the pro-national park campaign group, said it would be extremely difficult to build the stadium if it was inside the park's borders.

He said: "This is really one of the reasons for having a national park because the park authority would put the interests of the park first.

"So this is one of the things that is unlikely to happen in a national park."

Albion chief executive Martin Perry said: "We will wait and see what they come up with before we make any comment."

The first public consultation will be followed by a second, involving councils, and there will almost certainly be a public inquiry before the park is created, probably in 2003.

The Countryside Agency stressed any draft boundaries agreed tomorrow could still change.