NTL is being sued by its banking adviser Morgan Stanley for more than £7 million sterling (€10.7 million) in unpaid fees, it has emerged.
The company has confirmed Morgan Stanley is pursuing it for the allegedly unpaid fees dating back to 1999.
NTL is currently deciding whether to contest the claim, but a spokeswoman says the group believes it has grounds to object to it.
However, she declined to comment further due to the pending legal action.
Morgan Stanley is currently advising NTL on its exit from Chapter 11 bankruptcy protection.
The bank, which is advising the group alongside Credit Suisse First Boston and JP Morgan, is expected to earn up to €20 million (£12.4 million) worth of fees for its role in helping the group restructure its £6.9 billion-worth of debt.
Morgan Stanley has had a close relationship with NTL, advising the group on its £8.2 billion takeover of Cable & Wireless Communications in July 1999 which made it Britain's biggest cable company, as well as several bond issues.
The group, whose target of leaving bankruptcy protection by late November has already failed, recently said it expected to emerge in the "very near future", although it has not announced a new deadline.
Under the restructuring proposals NTL plans to become two businesses - NTL UK and Ireland and NTL Euroco, with its debt mountain converted into equity.