TWG's directors have authorised MacKenzie, its chairman and chief executive, to seek other backers and come back with a detailed bid before the deadline of March 21, which was set when he first approached them around February 11.
Before that deadline, they are not allowed to solicit other offers but yesterday the company revealed that it had been approached by other parties. Industry sources speculated that radio, books and music publishing business Chrysalis was among them.
Any offer would have to be accepted by TWG shareholders, including News Corporation and Liberty Media, which own more than half of the company between them.
The first sign that MacKenzie's offer was losing momentum came last week when News Corp appeared less ready to sell to MacKenzie than initially thought.
Now Veronis Suhler Stevenson is believed to have pulled out over differences of opinion with MacKenzie either about his role or the size of his stake in the company if the bid succeeded.
Yesterday, shares in TWG fell back 3.5% to 90p, the price at which MacKenzie's offer was set. Because the offer did not place any premium on top of the share price, analysts doubted how attractive it was to shareholders.
MacKenzie is believed to be pursuing the deal in order to expand TWG's portfolio of talk radio stations, while Chrysalis has been linked with a bid because it owns two talk stations, LBC and News Direct.
TWG owns national station TalkSPORT as well as 16 local radio stations. It will begin broadcasting in Edinburgh later this year after winning the city's FM licence in December and it has also submitted a bid for the Manchester FM licence.
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