Former Cable & Wireless boss Royston Hoggarth will become chief executive of BT Global Services' UK arm in September.
The UK provides roughly half of the division's £8bn yearly turnover.
Speaking to Computer Weekly, Hoggarth said he did not expect businesses to use BT both for IT and communications services.
There was much industry talk about "converged services" which bundled IT and communications into a single managed product, but Hoggarth said he was sceptical of its attractiveness to customers.
While at C&W, Hoggarth said he did not buy IT services and telecoms from the same supplier because he would have lost some of the pricing advantages that competition brings.
C&W had been one of BT's main customers, and Hoggarth said he had been impressed with its technical and problem-solving skills. He intended to apply those skills in the service of Global Services' customers. But first he wanted to hear what they were looking for.
His comments echoed the remarks of BT Global Services CEO, Francois Barrault, who said last month that he wanted the firm to develop a more intimate relationship with customers, to the point of sharing the risks and rewards of joint product development.
Hoggarth said many of his projects at C&W involved working closely with businesses to develop custom solutions. "There is a point where you go from 'mass customisation' to highly bespoke development," he said.
Hoggarth was coy about which business sectors BT will target first, but the FTSE 100, banking, central and local government will be high on his priority list. "I know many of the chaps from my time at C&W and at Logica and IBM before that," he said.
Referring to the credit crunch's effect on ICT budgets, Hoggarth said, "Unfortunately, I am old enough to have been through this cycle a couple of times. We are seeing less activity among the private equity groups, but more among the mainstream banks. We just have to do the basics well."
BT Global Services has more than 3,000 UK customers. They include KPMG, Unilever, NHS, Ministry of Defence and Department for Works and Pensions. UK customers contributed around £4.5bn of almost £8bn of BT Global Services' revenues in 2007/8. Nine out of 10 UK financial institutions use secure data networks from the company.
Royston Hoggarth CV
Royston Hoggarth was CEO of Cable & Wireless UK, Europe and US between 2003 and 2004. From 2001 to 2003, he was CEO of Logica's international business, overseeing the Middle East, India, South East Asia, Australia and Americas regions after a stint as supervisory managing director for Logica Mobile Networks. Prior to Logica, he worked for IBM. He holds several directorships with ICT and venture capital firms.