A leading mobile phone firm is warning the quality of services will go down if further mobile mast construction is hampered by campaigners.

T-Mobile, formerly One to One, says increased mobile phone usage has generated the need for more masts.

But campaigners say there remain questions over whether there are health risks associated with the masts.

Residents in many areas have been fervent in their opposition to the siting of antennae near homes or schools.

Mobile usage is still rising

But T-mobile has now taken on a more strident tone in its attitude to new masts.

It says if mast construction is halted or slowed, services will suffer.

The volume of mobile phone calls and text messages is expected to grow by 25% over the next three years and that is not taking into account the new third generation services.

But campaigners from the pressure group Powerwatch say that given public health fears, more controls on mast construction are needed.

Residents groups have suggested that until more is known about the effects low-level RF radiation may be having on the long-term health of children, mast construction should be limited in certain areas.

Many have also been angered about the placing of masts on low-level sites which do not require planning permission, and can be put up without protest.

Masts sited at petrol stations, churches, fire stations and particularly schools, have caused anger.

But mobile phone firms point to studies suggesting that masts near schools are well within international standards on electromagnetic emissions.