UPDATE 2-Telefonica says unaware of network deal with Vodafone

* Move would cut capex, boost profitability

* Telefonica shares up 0.07 percent, Vodafone up 0.8 percent

(Adds comments, share prices)

By Robert Hetz

MADRID/LONDON, March 17 (Reuters) - The head of the Spanish division of Telefonica (TEF.MC) said on Tuesday he was unaware of a new network sharing deal with rival Vodafone (VOD.L) after a newspaper reported it was in the works.

"The last agreement to share networks with Vodafone is 2007, but there is nothing new to say," Guillermo Ansaldo, chairman of the Spanish division told reporters on Tuesday.

Spanish financial daily Expansion said Telefonica and Vodafone were considering extending a possible network-sharing agreement beyond Britain to the rest of the world, but did not cite its sources.

Telefonica said it already shared some infrastructure with Vodafone in Spain, including systems alongside fast-speed rail lines.

Network sharing deals are seen by analysts as ways to cut costs by sharing investments and boosting profitability. In addition to Britain and Spain, the two operators are both present in Germany, Ireland and the Czech Republic. Last week, Britain's Guardian newspaper reported that talks between the two companies to pool their networks in Britain were at "an advanced stage" with an announcement due in the next few weeks.

Vodafone has declined to comment on the reports.

At 1332 GMT, Telefonica's shares were up 0.13 percent at 15.10 euros, while Vodafone's shares added 0.75 percent to 121.25 pence.

"This is no more than a cost savings exercise, which is not surprising given the current environment. The big telcos have already announced plans to cut capex and sharing networks is another step to beat the crisis," an analyst in Spain said.

"Any news that implies reducing costs and improving margins is well received by the market these days," Banesto Bolsa analysts said in a note, but added it was too soon to determine the impact of an alliance on the operators' bottom line. (Reporting by Robert Hetz; Additional reporting by Paul Sandle and Judy MacInnes; Writing by Tracy Rucinski; Editing by John Stonestreet and Jon Loades-Carter)