(Recasts with share reaction, Oi filing on option given to Portugal Telecom)
SAO PAULO, Sept 17 (Reuters) - Shares of Brazilian wireless carrier TIM Participações SA rose on Wednesday after its parent company, Telecom Italia SpA, said it is not in talks to take over rival Grupo Oi SA.
TIM said in a securities filing that Telecom Italia had denied any negotiations following a Bloomberg report on Tuesday of a potential deal to counter Spanish rival Telefonica SA in Latin America's largest market.
Shares of TIM rose 3 percent in Sao Paulo trading, among the biggest gains on the Bovespa stock index, after slumping 4 percent on Tuesday.
Oi shares also gained 3 percent, touching a two-month high. In Milan, shares of Telecom Italia closed up 1.6 percent at 0.91 euro
In a separate filing on Wednesday, Oi gave details of a call option granted to Portugal Telecom SGPS SA under a revised merger agreement.
Portugal Telecom will have the right to acquire more shares or their equivalent in cash over the next six years. The strike price for the option is 1.8529 reais per Oi preferred share , 2.0104 reais per Oi common share, and 2.0104 reais per share in the combined company, known as CorpCo.
The companies drafted the new accord in July, shareholders approved the deal this month, and Oi's board of directors approved the terms on Wednesday.
Shares of Portugal Telecom closed up 1.1 percent at 1.80 euros. (Reporting by Brad Haynes and Marcela Ayres; Additional reporting by Alberto Alerigi Jr.; Editing by Leslie Adler)