SAO PAULO, Aug 8 (Reuters) - Groups vying for control of

Brazilian petrochemical producer Braskem ( BAK ) are expected

to resist a sale of its U.S. assets, three people close to the

discussions told Reuters.

Brazilian chemical company Unipar is in talks to

acquire Braskem's ( BAK ) polypropylene plants in Texas, Pennsylvania,

and West Virginia for around $1 billion, according to a report

on Thursday by Brazilian newspaper O Globo and a source familiar

with the talks.

Braskem ( BAK ) and Unipar confirmed on Friday they were discussing

the sale of unspecified Braskem ( BAK ) assets.

Shares of Braskem ( BAK ) were up about 3% and those of Unipar jumped

almost 9% on the Sao Paulo stock exchange on Friday.

However, neither of the parties vying to assume a controlling

stake in Braskem ( BAK ) are interested in selling the U.S. assets,

sources said on condition of anonymity.

Brazilian businessman Nelson Tanure, who entered a 90-day period

of exclusive talks with engineering group Novonor, formerly

known as Odebrecht, opposes the idea, one of the sources said.

Private equity management firm IG4 Capital, which hatched a

rival plan to pool Novonor's bank debt and swap it for control

of Braskem ( BAK ) once Tanure's exclusive negotiations expire this

month, would also likely oppose a sale of the U.S. plants,

without a comprehensive plan for the future, another source

said, noting that these holdings are important.

A U.S. asset sale would also run counter to Braskem's ( BAK ) stated

strategic plan, according to a third source.

Braskem ( BAK ) and Unipar declined to provide further details on the

assets. Tanure and IG4 declined to comment.

Braskem's ( BAK ) CEO on Thursday denied any interest in selling the

U.S. assets.