UPDATE 1-S.Korea NPS to sign $1.3 bln HSBC building deal

* Signing expected early next week

* NPS beat Deutsche Securities over the deal -paper

SEOUL Nov 13 (Reuters) - South Korea's National Pension Service (NPS) will sign a 800 million pound ($1.33 billion) deal next week to buy HSBC's (HSBA.L) head office building in London, an official at the world's No. 5 pension fund said on Friday.

"We are in talks to close (the deal) early next week," an NPS spokesman said by telephone.

The Maeil Business Newspaper reported that the South Korean pension fund had trumped Deutsche Securities to secure the purchase, and that HSBC would lease the building for the next 18 years, without citing a source.

HSBC has been mulling the sale of its premises on New York's Fifth Avenue, the Champs Elysees in Paris and London's Canary Wharf for several months to boost its balance sheet. [ID:nLT588764]

NPS, with around $200 billion in assets, plans to invest $3 billion in real estate in Tokyo, Sydney, New York and London this year.

It appointed real estate investment manager Rockspring to take charge of its central London property acquisitions strategy. [ID:nL4405102]

Last week, the pension fund announced 268 million pounds worth of office deals in London. [ID:nL2565002]

Asian pension and sovereign wealth funds with large war chests are on a shopping spree for choice office buildings in global capitals, striking while there are bargains to be had in the wake of the global credit crisis.

($1=.6034 Pound)

(Reporting by Kim Yeon-hee and Lee Soo-jung; Editing by Jonathan Hopfner)