LONDON, May 8 (Reuters) - Italy's largest insurer Generali

BGN.MI has secured fund manager M&G as the first tenant for its 420 million pound London office development, allowing it to start construction of the 13-storey tower.

Generali Real Estate said on Thursday that M&G, the fund management arm of Prudential PRU.N , had agreed to take a 20-year lease to occupy three-quarters of the 40,000 square metre office development as its new global headquarters.

"This development in the heart of London is a high-quality investment that demonstrates the group's commitment to the City of London and to expanding its global property portfolio," said Nikhil Srinivasan, chairman of Generali Real Estate which manages a 30 billion euro ($41.77 billion) portfolio.

The scheme, 10 Fenchurch Avenue, sits in the City of London's insurance neighbourhood close to the Gherkin tower. Alongside 13 floors of office space, it will also contain shops and a roof garden. Generali first attained planning consent for the scheme in 2008.

London's City financial district has started to see a pickup in demand for space from companies in recent months after years of little activity as many had shelved planned office moves amid

the economic uncertainty.

In January, wealth manager Schroders SDR.L signed a pre-let to occupy the whole of the London Wall Place development, a 310,000 square foot scheme by Brookfield Office Properties BPO.TO and Oxford Properties.

($1 = 0.7183 Euros)

(Reporting by Brenda Goh; editing by Kate Holton)

((brenda.goh@thomsonreuters.com)(+44 020 7542 2230)(Reuters Messaging: brenda.goh.thomsonreuters.com@reuters.net))

Keywords: GENERALI LONDONPROPERTY