The Lowdown: Bill Allan is that rare thing in the telecoms industry: a consistent performer.

The question is not a complicated one: have you been approached to head Cable & Wireless? "I am not interested in becoming chairman of the company," retorts Bill Allan. But the chief executive of Thus, a rival in the telecoms market, knows this isn't what's being asked.

The question is rephrased: have you been approached to replace Graham Wallace, C&W's beleaguered chief executive?

It's a fair question. For a month there has been speculation that Allan is in the frame to replace the C&W chief, who has presided over arguably the most disastrous period in the company's history. And on the very day of our interview, the lead business story in many newspapers speculated about who might be next in the hot seat at C&W.

But Allan, playing the diplomat and knowing that officially C&W is searching only for a new chairman, says with a smile: "The chief executive's job is not available."

In recent months, Allan – one of the more outspoken leaders in the telecoms industry – has won praise from the City as safe and steady pair of hands. The Scotsman may have seen a dramatic fall in his company's share price, but who hasn't in the telecoms sector? Thus has stuck to what it set out to do. It has built a UK business and, as result, Allan is now one of the longest-standing chiefs of a telecoms company. Many shareholders would love to see him replace the unpopular Wallace at C&W.

Says one fund manager: "The thing with Bill is he says something and then delivers on it. He is a consistent performer."

The other rumour doing the rounds about Allan is that, rather than running C&W, he's interested in buying its UK business, once known as Mercury. On this, Allan is a little more forthcoming: "We have a watching brief on C&W. There could be some strategic rationale in integrating the old Mercury business with Thus."

Maybe both rumours are true. Perhaps neither is. But there are few people outside C&W who know the company better than Allan. Before arriving at Thus, originally created by Scottish Power, he worked for 26 years at C&W, latterly heading most of the company's vast international operations.

Despite being a big competitor, Allan says he's "very sad" to see C&W suffering (shares down 95 per cent over 12 months after four consecutive profits warnings). "The tragedy of C&W is that the company had a history of building up customer bases around the world. Sadly, many of those bases were sold off, and in telecoms you don't make money just out of owning cables," he says .

Like most telecoms companies of its generation, Thus was set up as a rival to BT. It shares peaked at 844.5p in March 2000 and it briefly entered the FTSE 100. Weeks later, the telecoms bubble burst and the market began to realise that competing against a former monopoly was at best very tough. On Friday, Thus's shares closed at 9.2p.

Allan is an outspoken critic of BT and of the way it is regulated under Oftel. "BT is abusing its market dominance and we have lodged a number of complaints with Oftel. It is taking advantage of the market, but it is also taking advantage of the regulator. BT's regulatory department is probably a lot bigger than the whole of Oftel."

Surprisingly for a businessman, Allan is even calling for tougher and "heavy-handed" regulation from Ofcom, the new media regulator expected to replace Oftel late this year. In particular, he is worried that BT, under Ben Verwaayen, will exploit the hiatus created by the changeover. "BT is very skilled at playing the political game." Flippantly, he adds: "I find it interesting that Mr Ben Verwaayen heads a committee, or something, looking into – I don't know – lonely women. That is interesting for a guy running a telecoms company that has a large debt burden and is going through a huge amount of change."

BT is also on Allan's blacklist of companies that have sold telecoms services at cost or below in an attempt to improve revenues. He believes that last year BT was overly aggressive in the pricing of its internet services.

"We can't compete with that. We'd go out of business. Some companies have been doing this to get some news flow going to try and reassure their existing customers the business is viable." He goes on to claim: "Energis, for example, reviewed its contract with Freeserve below the original contract value."

Allan accuses WorldCom, the scandal-rocked US telecoms operator, of similar tactics. "I'd rather have a smaller business that has a strong bottom line," he says. "We're still expanding our margins. But we've had to spend a long time convincing customers we aren't going the same way as Energis – even C&W now."

On paper there is little chance of this happening to Thus. In November the Glasgow-based company posted a £17.1m net loss in the three months to 30 September, from £21.6m in the same period the year before. But it stated that it was still on track to be cash-flow positive by March 2004. A refinancing deal completed around Christmas 2001 means that, barring disaster, Thus has enough cash with a bit to spare to see it through to break even.

The problem is, the City is still paranoid about telecoms companies, and many investors avoid loss-making ones. Thus has experienced a minor rally in its shares since September but is nevertheless valued at a measly £127m. With such a low rating, what's the point of being quoted at all? Again, there has been speculation that Allan may take the company private if Thus's shares don't see any improvement in the next few months.

But Allan dismisses any plans to de-list: "I don't think there's any evidence to suggest there isn't a future for the company on the [stock] market. If you look at the volume of shares traded, there's certainly interest in the stock and the story. Twelve months, maybe two years, down the line and the capital markets could be our best friends."

But he says that won't happen until "there's some clarity in the UK market structure". By which he means until companies such as Energis, WorldCom and Global Crossing have "re-established their balance sheets". He omits C&W from this list, perhaps deliberately. But by his own definition, the future of the UK telecoms market could be in his hands.