Telewest had planned to swap the �3.5bn of bond debt for equity in a deal which would leave shareholders with 3% of the new shares.

But, under pressure from the bondholders, the company is now considering a new arrangement which would see them getting a bigger slice of the new shares.

"In order to obtain the support of certain of the company's bondholders, the bondholder committee is requesting certain changes to the economic and other terms of the preliminary restructuring agreement," Telewest said in a statement.

Telewest, like other telecoms companies, piled up debts to fund acquisitions during the hi-tech boom only to find its assets are no longer worth what it paid for them.

Further negotiations

Telewest said it continued to believe the restructuring would be concluded successfully, but further negotiations would be required with the bondholders and other major stakeholders.

"While we are disappointed with this development, we are in the final stages of these discussions and therefore the restructuring process," Managing Director Charles Burdick said in a statement.

Telewest announced its preliminary agreement with bondholders last September.

The group said it was now close to filing restructuring documentation publicly, but needed bondholder support for a final, binding agreement.