At 91p a share, the cash offer trumps the 90p-a-share offer made in February by Kelvin MacKenzie, the Wireless Group chief executive and chairman, who is unlikely to stay with the company in the event of its sale to UTV.
MacKenzie stands to make around £7m from UTV's swoop, which values his 6.4% stake in TWG at £6.1m and, were he to depart, would bring a payoff of about £800,000.
TWG's three independent directors and board members have committed to accept the offer and the deal can only be stalled if UTV decides to withdraw.
Buying TWG extends UTV's business from the Irish media sector into the highly competitive English and Scottish radio market. It has landed one of only three analogue national stations in TalkSPORT, which also has a digital national presence, as well as 16 local stations.
UTV owns the ITV franchise for Northern Ireland and since 2000 has assembled a collection of four local radio stations across the Republic of Ireland. In March, it won new FM licence for Belfast with an easy-listening music format aimed at the over-45s.
Until now, its only presence outside Ireland was the part-owned Juice FM in Liverpool as part of a consortium called Absolute Radio. However, it has eyed up other UK radio companies in the past, including Scottish Media Group, which it attempted a £400m bid for in early 2004.
John McCann, chief executive of UTV, said the acquisition would provide a cornerstone for a broader radio strategy for UTV in mainland Britain.
Patrick Cox, the senior independent non-executive director of TWG, said: "We believe that the combination of Wireless and UTV will create a strong competitor in the UK media market, with a diversified portfolio in TV and radio and a platform for expansion in the new digital channel formats."
UTV sees Wireless's interests in local digital multiplexes as giving it a way of exploiting the anticipated growth in digital radio, which is expected to see 13m homes in the UK will have digital radio in 2008 up from approximately 1m in 2004.
Its offer document reveals that it is making the deal on the basis of forecasted growth in radio advertising expenditure of 3.4% this year.
The Irish company estimates that the acquisition will contribute to profits straight away and that its will be able to derive £1.5m in cost savings in the financial year to the end of 2006.
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