LONDON — The consolidation of the British cable industry has taken another step forward with the announcement that NTL Inc. has agreed to acquire ComTel for £550 million ($902 million).

The deal, along with NTL’s previously announced takeover of Comcast’s U.K. franchises, will almost double the size of the American company’s U.K. cable empire.

The number of homes within NTL’s franchise areas will increase from 2 million to just under 4 million. Of these, 2.2 million already have access to the cable network, and 668,000 subscribe. NTL is in the process of completing construction of the networks.

Nasdaq-quoted NTL is acquiring ComTel from Vision Networks III, a wholly owned subsidiary of the Dutch telco Royal PPT Nederland.

Under the two-stage deal, NTL has paid $451 million cash for certain ComTel properties, and will subsequently pay another $328 million in cash and $123 million in stock for the remainder, subject to certain corporate reorganizations within ComTel.

The first part of the transaction has been financed by extending NTL’s existing loan with Chase Manhattan Bank.