UPDATE 1-Eidos warns on sales as new Tomb Raider disappoints

* Says may have to talk to banks over lending covenants

* Shares fall 28 pct

* Co encouraged by reaction to 'Batman: Arkham Asylum' game

(Adds details, analyst comment, shares)

LONDON, Jan 9 (Reuters) - Britain's Eidos Plc. EIDE.L, the developer of the 'Tomb Raider' computer games series, cut its sales forecast and said it may need to talk with its bank over the terms of loans, sending shares in the company 28 percent lower.

The company said on Friday that its 'Tomb Raider: Underworld' release had performed below expectations in the United States, and total sales for the year would be in the range of 160 million to 180 million pounds ($244-274 million).

That compared with previous guidance of 180 million to 200 million pounds.

"We have passed our peak net debt position and we retain sufficient headroom within our committed banking facility but given revised profit expectations we may need to enter into discussions with our lending bank regarding our June 2009 covenants," Eidos said in a trading update.

The company said it was encouraged by the reaction to its forthcoming Batman: Arkham Asylum game, which was trailed on DVDs of movie 'The Dark Knight' at Christmas.

Shares in the group, which had already lost 95 of their value in the last two years, were down 23.2 percent at 13.25 pence at 0952 GMT, valuing the company at about 32 million pounds.

Analyst Nick Batram at house broker KBC Peel Hunt said the downgrade was clearly disappointing, but given the broader consumer market perhaps not that surprising.

"Batman is a major second-half launch and given its importance to Time Warner (TWX.N), we still expect this to happen," he said.

"However, the Batman launch will be working-capital consumptive towards the end of H2 and the group may have to speak to its lenders." Batram said. ($1=.6561 Pound) (Reporting by Paul Sandle; editing by Simon Jessop)