UPDATE 3-Turkey says no Turk Telekom offering under way

* Privatisation body says no offering process under way

* 15 percent stake to be offered by Q1 2010 - newspapers

* Shares fall 2.9 percent

(Releads, updates share price)

ISTANBUL, July 3 (Reuters) - Turkey's privatisation body has not begun the process of selling a second tranche of state-owned shares in Turk Telekom (TTKOM.IS), it said on Friday after reports an offering was planned for 2010.

Two Turkish newspapers said Turkey's Privatisation Administration was planning to sell a 15 percent stake in Turk Telecom, which is also active in the internet service provider and mobile sectors, by the first quarter of next year.

"No process has been recently started for the privatisation of any shares in Turk Telekom owned by the Treasury," the administration said in a statement.

Shares in Turk Telekom traded down further at 2.9 percent at 4.64 lira after a suspension on the shares was lifted, pending an announcement from the sell-off body.

Selection of an investment bank to advise on the process was expected to take place by September, the Star daily reported.

Turk Telekom, controlled by Dubai-based Oger Telecom, was listed on the Istanbul bourse in May 2008 when the government cut its stake to 30 percent by listing a 15 percent holding. Shares in Turk Telekom have risen some 50 percent this year.

Turk Telekom was privatised in 2005 with a 55 percent block sale bought by Oger Telecom.

The company, which has said it was targeting 8-10 percent growth in 2009, is looking to invest as much as $1 billion in acquisitions this year. Its first-quarter net profit fell 27 percent to 291 million lira ($190 million). (Editing by Hans Peters and Mariam Karouny) ($1 = 1.528 Turkish lira)