Sir Richard is thought to be keen on a sale

The cable TV firm began a review of the business a month ago, after receiving a �5.5bn offer from an unnamed bidder.

Virgin said it had decided to give potential suitors more time to enable them to put together a deal in a "more stable debt market environment".

Virgin shares have been under pressure after a row with rival broadcaster Sky and a drop in customer numbers.

While TV customer numbers were "roughly flat" at three million users in the three months to June, Virgin had lost 46,900 customers in the previous three months to the end of March.

Rivals clash

Analysts blamed the slide on the row with BSkyB which led to Sky withdrawing its channels, including Sky One, from the UK cable group in a dispute over fees for those services.

The two had also been involved in an earlier spat after Sky thwarted Virgin's efforts to take over ITV.

"As a consequence of this review and the resulting process, potential strategic and financial counter-parties have continued to confirm a strong ongoing interest in a transaction," Virgin said in a statement.

"Virgin Media's financial advisers have recommended that Virgin Media extend the process until these parties can complete their proposals in a more stable debt market environment."

Sell-off hope

Virgin is not the only company to postpone its potential sale as a result of difficult market conditions, as interest rate rises have increased the cost of debt.

Cadbury has postponed the demerger of its Schweppes drinks business for the same reason.

Virgin founder Sir Richard Branson - the largest shareholder in the business with a 10.5% stake - is believed to be keen for the firm to be sold.

Market talks suggests a number of private equity companies could be interested in the media firm, including Providence Equity - which owns a number of US and European TV companies.

However private equity group Carlyle, widely believed to be behind last month's �5.5bn approach, is thought to be the front-runner.

Carlyle has substantial experience in the cable market and owns Insight Communications, which is among the 10 largest cable firms in the United States.

Reports suggested the group would be keen to distance itself from Sir Richard Branson and the Virgin empire in order to improve relations with BSkyB and Rupert Murdoch.

Virgin Media was formed last year by a merger between Virgin Mobile and NTL Telewest.