The Competition and Markets Authority said the 10-billion-euro ($11.05 billion) deal would harm competition and could lead to higher prices or lower quality services for mobile carriers. To address these concerns, Cellnex will have to dispose of 1,000 towers, it said.

The company's CEO Tobias Martinez said in a statement their presence in Britain as a 'neutral operator' will contribute to speed up, improve and expand the mobile phone coverage.

In late 2020, Cellnex had announced the acquisition of the 24,600 phone masts operated by CK Hutchison in Austria, Denmark, Ireland, Italy, Sweden and Britain.

Cellnex said in a statement Britain's watchdog regulatory approval was the last-pending for the CK Hutchison deal to be completed.

The Spanish company had said last month it expected the sales induced by anti-trust concerns in France and Britain would bring 1.1 billion euros. French anti-trust regulator had ordered Cellnex to sell 3,200 masts in that country.

($1 = 0.9050 euros)

(Reporting by Joan Faus, Inti Landauro and Aby Jose Koilparambil in Bengaluru; Editing by Shailesh Kuber, Alexandra Hudson)