Patricia Hewitt, the Trade and Industry Secretary, today gave the go-ahead for the country's two largest independent terrestrial broadcasters, Carlton and Granada, to merge in a deal estimated to be worth £3.8 billion. The merger will bring together under one roof 12 of the 15 ITV regional franchises. Here, Raymond Snoddy, Media Editor of The Times, explains some of the ramifications:

What effect is the merger likely to have for the viewers? Will the programmes be any better?

Nobody can guarantee better programmes, least of all the merged Carlton-Granada, which will form the new company, ITV plc, before the year is out.

Charles Allen, the executive chairman of Granada and one of the prime movers in the deal, did say today: "ITV will have more investment in programmes than any other commercial broadcaster in Europe.

"Our viewers and advertisers will see better television, packed with the most popular British programmes, backed by an absolute commitment to quality in everything from news to drama."

Mr Allen and his counterpart, Michael Green at Carlton, expect to pay for this with a saving of at least £55 million a year from the merger, giving them more money to invest in expensive categories of programming, such as drama - which can easily cost more than £500,000 per broadcast hour to produce.

A simplified company structure should also help.

"The days of different companies with different agendas working in a 1950s federal system are finally at an end," Mr Green said.

The merged company will have three divisions - news, broadcasting and programming.

Why are the advertisers opposed to the merger?

Advertisers would like a stronger ITV to deliver larger commercial audiences, but they are afraid that a single ITV advertising sales force controlling 52 per cent of all television advertising in the UK will act against their interests. Basically, they think the ad rates will go up.

At the very least, they wanted Carlton and Granada to be forced to sell their sales houses to protect competition in advertising sales. But if this proposal had been forced through, it would have made the new ITV plc less attractive to American broadcasters who might want to buy into the new company.

Times Recommends

• C&G axed - 1,660 jobs to be lost
• UK house prices rise 1.1% as buyers return
• Mixed reaction to US banks repaying bailouts