But it explained that the deal, which angered some shareholders, had been forced by British Telecom's refusal to allow BT Cellnet to bid separately for a new mobile phone licence.
BT agreed in July to buy the Securicor stake for £3.15bn, giving it full control of the mobile phone company.
"Under the proposals, £3.02bn of the consideration payable by BT will be paid directly to the shareholders of Securicor," the firm said in a statement.
The larger than expected payout to investors is the equivalent of 500p per share. But it will be paid only if they approve the sale of the group's Cellnet stake.
Originally, the group had planned to return £2.8bn to shareholders, but was reported to have revised its plans after failing to find any suitable acquisitions.
Securicor is understood to have looked for deals in cash delivery, security personnel and parcels distribution. Its failure to find a suitable purchase is expected to prompt some speculation that it could become a takeover target.
BT Cellnet is the UK's second largest mobile telephone operator with more than five million customers. Vodafone is the market leader, with Orange and One-2-One the runner-ups.
Explains sale
Although Securicor was not able to gain as much as it might have from a sale on the open market, the sale gives the company an impressive return on its original investment of just £4m in Cellnet in 1983.
There has been some opposition to the sale from shareholders who believe that the price agreed for the stake in the UK's second largest mobile phone operator was lower than it should have been.
But Securicor said there were two reasons why it sold its stake.
First, it had discovered that London Stock Market rules would not allow it to demerge and list its stake in Cellnet separately on the stock market.
Secondly, it was concerned about the bidding for the next round of digital mobile licences. Under government rules, both BT and BT Cellnet would not have been allowed to bid for the third generation of licences.
Securicor said during the course of negotiations it became clear that BT would not, as Securicor wished, support an application by BT Cellnet for a third generation mobile licence.
Instead BT, supported by the BT Cellnet management would bid for a licence itself, seek to conclude complex arrangements with BT Cellnet, whereby BT Cellnet would be able to provide third generation services supplied by BT.
It was the block on Cellnet's future development that led Securicor to consider the sale.
Smaller group
The plan means that Securicor will be a much smaller group, with just three divisions, involving security, distribution, and communications.
It says the new group will show a pre-tax profit of around £31m, and will pay an interim dividend of £4m.
The security business was performing strongly, with improving margins.
The distribution division has been affected by the slow-down in the retail sector in the UK and the one-off restructuring costs following an acquisition last year.
And losses would be around the same level in the communications division.
"The Board of Securicor believes that the New Securicor group has a sound platform for future growth," the company said.
BT's Cellnet buy faces challenge
(18 Aug 99 | The Company File)
BT gobbles up Cellnet
(27 Jul 99 | The Company File)
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