UPDATE 1-Gazprombank sells control of petchem giant Sibur

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MOSCOW, April 29 (Reuters) - Gazprombank, the banking arm of Russian gas giant Gazprom GAZP.MM, agreed to sell control of petrochemical firm Sibur for a total of $5.4 billion to Sibur's managers, giving a generous grace-period for the cash component.

The deal is part of the bank’s strategy to get rid of non-core assets, which raised investors’ eyebrows after Sibur, heavily reliant on gas supplies from Gazprom, was first transferred from Gazprom to Gazprombank and dubbed a non-core asset.

Gazprombank said in a statement on Tuesday the deal’s total valuation comprised a cash component of 53.5 billion roubles ($2.27 billion), plus 25 percent of Sibur’s 2007 net profit that will be paid to Gazprombank in addition to the assumption of Sibur’s heavy debt by the new owners.

The cash component will be split into 16.6 billion roubles that should be paid immediately, another 11.9 billion payable within three months with the rest to be paid within three years.

Sibur is a smaller version of the former Soviet Union’s petrochemical industry, which disintegrated in the early 1990s following chaotic privatisations under President Boris Yeltsin.

But it was reinvigorated by Gazprom at the end of the last decade.

The world’s largest gas producer, which supplies a quarter of Europe’s gas, spent billions of dollars to consolidate over 30 gas processing plants and rubber, plastics and tyre factories under the Sibur brand.

Sibur’s previous management, led by chief executive Yakov Goldovsky, almost secured the company in a management buyout deal with Gazprom’s former managers.

But Goldovsky went to prison for a few days after Gazprom’s new chief executive and ally of president Vladimir Putin, Alexei Miller, embarked on a campaign to regain major assets lost under previous managers early this decade.

At that time Miller valued Sibur at over $2 billion, while analysts have recently put Sibur’s value at up to $10 billion.

Gazprom said Sibur was a non-core business when transferring it to Gazprombank last year and said it wanted to focus on gas, oil and power production. Gazprom also plans to divest Gazprombank, Russia’s third largest bank.

The stake of 50 percent plus one share in Sibur will be bought by Hidron Holdings Ltd in which five Sibur top managers are beneficiary stakeholders: chief executive Dmitry Konov, senior executive vice-president Vladimir Razumov and vice-presidents Vitaly Baranov, Alexei Filippovsky and Mikhail Kirisalov.

The deal was organised and is being partly financed by investment fund United Capital Partners. (Reporting by Dmitry Zhdannikov; editing by David Cowell)