UPDATE 1-Oslo bourse holds trade in Cisco target Tandberg

(Adds Bloomberg report, background)

OSLO/LONDON, Oct 30 (Reuters) - Oslo's bourse halted trade in Cisco (CSCO.O) takeover target Tandberg (TAA.OL) after a media report said Cisco might drop rather than raise its $3 billion bid if it did not win 90 percent shareholder approval.

"Oslo Bourse is investigating whether some participants have access to different information in relation to evaluating the value of the company's shares," the stock exchange said in a statement on Friday.

Shares in videoconferencing company Tandberg were down 2.7 percent to 152.30 Norwegian crowns ($26.92) when trading stopped, below Cisco's bid of 153.50 crowns per share.

One analyst said he believed the shares were halted due to a Bloomberg report that Cisco would strongly consider walking away if it could not secure approval from investors with 90 percent of Tandberg, citing a person familiar with the transaction.

Cisco, the world's biggest network equipment maker, launched a one-month tender on Oct. 9.

Neither Cisco nor Tandberg was immediately reachable for comment. ($1=5.658 Norwegian Crown) (Reporting by Oslo newsroom, Georgina Prodhan in London and Christoph Steitz in Frankfurt; editing by Simon Jessop)