Telecoms group BT announced today that it had won a £18m deal to install up to 180 of its new internet kiosks at Heathrow, Gatwick and Stansted airports - the largest contract of its kind so far won by its payphones division.

BT is to replace about a third of the existing payphones at the airports with the web-enabled machines. It will also continue to manage the airports' remaining 350 basic payphones as part of the five-year deal with airport operator BAA.

The group has been following a programme of replacing standard payphones around the UK with new internet kiosks that allow people to surf the internet and send emails and text messages as well as to make calls.

It currently has about 1,500 of the kiosks and expects to have 20,000 within the next five years. The company plans to cut the number of basic payphones around the UK by about 30,000 to about 100,000 in the next two years.

A BT spokesman said the company will still have about 23,000 more payphones at the end of that programme than it had when the company was privatised in 1984. "There is still very much a future for payphones," he said.

Paul Hendron, director of BT Payphones, called today's deal with BAA - which runs seven UK airports - "a pivotal win".

"These airports are prime sites with a total of more than 112 million passengers passing through them each year," he added. "It demonstrates the massive potential for BT internet kiosks."