SAO PAULO (Reuters) - British America Tobacco Plc's offer for the 24.7 percent stake it does not already own in Souza Cruz SA (>> Souza Cruz SA) topped the value per share calculated in an appraisal by as much as 21 percent, giving a boost to a planned buyout of Brazil's largest cigarette producer.

In a securities filing, Souza Cruz said BAT - as British American is known - submitted a request with regulators for a tender offering. The filing did not say when the tender offering would take place.

Last week, BAT offered to pay 26.75 reais in cash for each share of Souza Cruz, valuing the buyout at $3.53 billion. That is 13 percent above Souza Cruz's closing share price on Friday and represents a 30 percent premium to its volume-weighted average closing price over the last three months.

The filing included an independent appraisal on the value of Souza Cruz shares carried out by investment banking firm NM Rothschild & Sons. The appraisal put the fair economic value for the stock between 22.09 reais and 24.54 reais.

The buyout would give the producer of Dunhill cigarettes full control over Souza Cruz, which has about 80 percent of Brazil's market. BAT last considered a Souza Cruz buyout almost five years ago, but the plan foundered due to a strong Brazilian currency.

Souza Cruz has more than 5,000 minority investors in Brazil, including a large chunk of retail investors who have kept the stock in their families for two or three generations.

A BAT buyout of Souza Cruz would come at a time when a number of foreign companies are delisting their Brazilian subsidiaries, a sign of confidence that they can better navigate Brazil's rough economic waters without pressure from minority investors.

BAT has hired Deutsche Bank AG, UBS AG and Banco Santander Brasil SA to manage the tender offering.

(Reporting by Guillermo Parra-Bernal; Editing by Alan Crosby)

Stocks treated in this article : British American Tobacco plc, Souza Cruz SA