Both telecom companies were expected to lead the drive to bring broadband internet access to homes and offices across the country, in competition with British Telecom (BT).

But they are thought to have lost patience with BT's apparent reluctance to open up local telephone exhanges for engineers to install broadband equipment.

The so-called 'unbundling' process is being overseen by Oftel, which has attempted to prevent BT exploiting its local monopoly.

Deadlock

WorldCom had chaired Oftel's broadband implementation working group, which led negotiations with BT over how rival operators could gain access to its local telephone network.

But it now appears to have quit the process in frustration, along with rival Global Crossing.

Neither company was on the list of 35 companies which have formally asked BT for access to local exchanges, it emerged on Thursday in a Financial Times article.