British Telecommunications Plc said yesterday that it plans major price cuts for all its customers next month, and it is to abandon its system of unit charging and will charge customers according to how many seconds a call actually lasts – the system already operated by Mercury Communications Ltd: the Office of Telecommunications said the savings for phone users would total about UKP350m in the very near future, but that BT still had a long way to go to meet its obligations on tightening the limit on average price increases; the new pricing structure will cut rental charges by up to 61% for about 3m infrequent users from April, but there is an increase of 73 pence per quarter in line rentals for residential customers; business exchange rentals will rise by UKP1.01 a quarter to UKP32.66; the Light User Scheme, which will replace the existing Supportline and Low User Rental Rebate schemes, will apply normal BT tariffs but offer a rebate to customers with a quarterly call bill of less than UKP10; and the one-off charge for a new user taking over an existing phone line was reduced by UKP11.78 to UKP25; through gritted teeth no doubt, since one of its selling points disappears, Mercury said it welcomed the move to change the pricing structure.