A council leader has threatened to pull his authority's headquarters out of Lewes if the town is included in a new South Downs national park.

East Sussex County Council leader Peter Jones questioned whether the council would continue to be based in Lewes in a letter to the watchdog drawing up plans for the park.

The letter provoked a row when councillors met to debate the Countryside Agency's proposals.

Councillor Jones told councillors it was a private letter to agency chairman Ewan Cameron.

He said he was trying to pressurise the agency into not including Lewes in the park but denied there was a threat to leave.

The town is inside draft boundaries the agency is consulting on until Thursday.

The agency is also consulting on what powers the ruling national park authority should have.

Conservative-controlled councils, who have reluctantly accepted the park, are fighting a battle to keep as much land as they can outside the boundaries and stop any of their powers being transferred to the new authority.

Coun Jones said: "What I was trying to ram home is there is an inconsistency in having a democratic organisation's headquarters in a town whose citizens would not have the same democratic rights as people elsewhere."

Liberal Democrat David Neighbour, who challenged Coun Jones about the letter, accused him of arrogance and said it should not have been sent without being approved by the council.

He said: "I think he is taking the council for granted. It has not been put to a formal vote.

"It goes against the known wishes of the people of the area."

A survey by Lewes District Council, which recently became only the second local authority to publicly support the park, found 67 per cent of people were in favour.

Ninety-eight per cent of respondents said they believed the Downs would have better protection because of the national park, while 72 per cent said planning controls would be stricter.

Planning is the only real power councils could lose to a national park authority, although the new body would be able to influence other decisions which affect the Downs.

It would predominantly be made up of county, district and parish councillors.

National park campaigner Paul Millmore said Coun Jones was playing party politics rather than doing what was best for Lewes and for the Downs.

He said: "For the Tories to say they wish to exclude Lewes is heartbreaking when the bulk of the people want it in."

The county council employs almost 1,300 staff at offices in Lewes. Most of them are at County Hall, which would need costly repairs to stay open.

District council leader Ann de Vecchi described the threat to leave as weird.

She said: "I don't see why the town should suffer just because a national park is created."