Global Radio's private backers are understood to have agreed to provide two thirds of the funding in cash to acquire GCap Media as they attempt to fight off turbulent markets and clinch a £371 million purchase of the owner of Capital 95.8.

It is understood that the financing has not yet been formally signed off. HBOS is expected to provide the remaining third of the funds as debt.

Global investors putting up the money include the Irish businessmen JP McManus, John Magnier and Dermot Desmond, and Michael Tabor, the father of Global's chief executive, Ashley Tabor.

GCap shareholders, who declined to be named, have expressed concern that Global might not be able to raise the funding given the recent turbulence in the markets and banks' reticence to lend money for deals.

Shares of GCap, which also owns Classic FM, are still well below the 225p offer price, indicating that investors believe the deal might not be done. GCap shares closed up 0.25p at 202p yesterday. The company's current market capitalisation is £333 million.

One source close to the deal last night insisted that the talks were on track and dismissed concerns that Global was having problems finding the money.

Sources close to Global have told The Times that the owner of Heart 106.2 and Galaxy has the financing lined up despite concerns over the credit crunch and prospects for the British advertising industry.

One said: “The gyrations of the last few days have not changed anything”. However, another source close to the deal conceded that, while the financing was in place, “you cannot take anything for granted in these markets".

GCap opened its books to Global Radio this month and the two sides are working towards a firm offer by March 26, the deadline set by the Takeover Panel.

Global Radio, which is chaired by Charles Allen, the former chief executive of ITV, bought Chrysalis Radio's stations last July for £170 million.

Many of GCap's leading shareholders are long-term investors that were stung by the £711 million merger of Capital Radio and GWR in 2005.

Fru Hazlitt, GCap's chief executive, has insisted that her strategy for the group, which became known as her “defence document”, would deliver more value to shareholders than an offer from Global Radio.

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