The company claims that this will give 99.6 percent of households and commercial premises access to broadband. About 570 exchanges, covering 100,000 premises, will remain outside the broadband pale. About 400 of these are in Scotland and the majority of the rest are in Wales, with the odd rural English exchange thrown in.
The move comes after a weekend of speculation over the possibility that new regulator Ofcom could dust off old plans and demand that BT be carved up in the same way as the gas and electricity industries; into a supplier arm and a customer arm.
A BT spokesman said: "Waiting for people in an area to hit the registration target was not a very joined-up way of doing it – we will save money on this planned approach, by linking some exchanges in a region, for instance.
"We will be in partnership talks about how to link the remaining households - by DSL, by wireless, perhaps by satellite."
Alison Ritchie, BT chief broadband officer, paid tribute to local campaigners for broadband access. She said: "The impact that local campaigners have had has been phenomenal. These local heroes have helped change the market and this in turn has contributed to our decision to take this approach."
The demand registration scheme, launched mid-2002, led to the upgrade of more than 2,000 exchanges, spurred by 880,000 individual registrations.
The BT spokesman pointed out that the new scheme would not only allow BT to plan its investment but "would give certainty to other providers".