Charles Allen, the openly gay former chief executive of ITV looks set to become one of the most powerful figures in the world’s radio sector.

Mr Allen, chairman of the private equity-backed Global Radio, has agreed to purchase GCap, the owner of Classic FM, Capital Radio and XFM for £375 million.

Just months ago, his company purchased Chrysalis Radio, the owners of Heart and talk radio station LBC 97.3.

The deal was reached just an hour after the city watchdog, the Takeover Panel, agreed to extend the deadline for merger talks between the two companies for a further 24 hours.

“We are delighted that the Board of GCap has unanimously agreed to recommend our acquisition of GCap,” said Mr Allen.

“We believe that this is a very strong business with brands and assets that are highly complementary to those of the Global Radio Group.

“The combined group will have an increased ability to hire and retain the industry’s best talent and obtain access to music industry content.”

The £375 million price tag is 18 per cent higher than Global’s initial 190p-a-share bid in December.

It’s 86 per cent higher than GCap’s share price earlier this year.

Last month, GCap surprisingly purchased internet start-up Welovelocal.com for £600,000.

The purchase by Global Radio is just months after newly appointed CEO Fru Hazlitt axed two of the firms digital radio stations, theJazz and Planet Rock, labelling digital radio as “economically unviable.”

The purchase, if approved by GCap’s shareholders, will give Global almost half of the UK radio advertising market.

An inevitable regulatory investigation will likely mean the company selling off some of its smaller stations.

Mr Allen quit ITV in August 2006 and was later replaced by Michael Grade as chairman.