UPDATE 1-Indonesia's Bakrie eyes 15 pct Indosat stake-sources

(Recasts lead, adds details, Qatar Telecom statement)

JAKARTA/DUBAI, June 26 (Reuters) - Indonesia's Bakrie group plans to buy a 10-15 percent stake in PT Indosat Tbk (ISAT.JK), the country's second-largest mobile phone firm, in the open market, sources familiar with the deal said.

The plan comes as Qatar Telecom (Qtel) QTEL.QA, which this month increased its stake in Indosat to 40.8 percent, confirmed that it would offer to buy the remaining shares in Indosat at 7,388 rupiah apiece, or a total of $2.6 billion.

Bakrie executives recently told investors that the firm planned to buy 10-15 percent of Indosat in the open market and hoped to increase its stake, sources said. One of the sources close to the group said the plan was at an early stage.

Singapore Technology Telemedia, owned by Singapore's state investor Temasek Holdings, sold its 30.8 percent Indosat stake to Qtel for $1.35 billion this month following a dispute over whether Temasek's units had violated Indonesia's anti-monopoly rules by owning stakes in the two leading mobile phone companies.

"This is, in our opinion, the first sign of the much-awaited consolidation in the telecom sector. So this presents a good opportunity, an attractive business opportunity for companies like Bakrie Telecom," said Dileep Srivastava, a director at Bakrie & Brothers (BNBR.JK).

Srivastava said that talk of Bakrie group buying into Indosat was "a rumour", but added that "we as a group are watching the development closely, whether there's an opportunity to enhance the value for our telecom operation and for Bakrie & Brothers."

The Bakrie group entered the telecoms sector and is keen to expand in one of Asia's fast-growing telecoms markets.

Temasek, through Singapore Telecommunications Ltd (STEL.SI), owns 35 percent of PT Telekomunikasi Selular (Telkomsel), Indonesia's largest mobile phone operator.

An Indonesian district court on May 9 ordered Temasek and its affiliates to sell their holdings in either Telkomsel or Indosat, upholding an earlier ruling by KPPU, the country's antitrust body.

In Qatar, shares of QTel closed 1.84 percent higher on Thursday on news that it plans to go ahead with its tender offer for Indosat, and outperformed the market, which posted its biggest one-day loss in more than a month, falling 1.76 percent.

"Investors are reacting to the Indonesian news," said Amro Motasim, chief trader at Doha-based Ahli Bank.

"The company is diversifying and they have lots of cash and it will be saturated with the arrival of a new company, Vodafone (VOD.L) in Qatar. By going internationally and globally it will guarantee its profit share," Motasim added.

Vodafone is due to begin operations in the first quarter of 2009, breaking Qtel's monopoly in running the country's mobile and fixed-line networks.

State-controlled or affiliated Gulf Arab telecom operators such as Emirates Telecommunications Co ETEL.AD have been expanding abroad as their home markets mature, spending billions of dollars on acquisitions and licences from Indonesia to South Africa. (Reporting by Harry Suhartono in Jakarta and John Irish in Dubai; Editing by Sara Webb)