British Land is understood to have exchanged contracts with Kajima to sell Orwell House in Soho for £22.7m.
The five-storey building at 16-18 Berners Street, W1, provides 28,000 sq ft of office space.
Tenants include Red Bus Media Group, skincare and wellness brand Perricone MD and the Alison Jacques Gallery.
British Land brought in Knight Frank to find a buyer for the property, while Fineman Ross advised Kajima.
This latest deal follows the REIT’s sale of mixed-use scheme Clarges Mayfair, W1, to Germany’s Deka for £177m in November as part of its strategy to recycle capital.
In November, British Land reported a pretax loss of £730m after its portfolio value plunged by £842m to £10.3bn during the six months to 30 September.
The fall in value of the properties was driven by a 14.9% decline in retail values, to £3.2bn, while its offices were down 3.1% to £6.7bn.
British Land declined to comment.
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