Canary Wharf developer Songbird Estates today warned it was not immune to the credit crunch despite so far avoiding much of the carnage in the property market.

The firm said the value of its property at Docklands fell 4.3% between the end of June and New Year's Eve, from £7.47 billion to £7.27 billion. Over 12 months, it was up 4.8%. The £200million writedown since summer was far better than many of its rivals with developments elsewhere in London and the UK, such as British Land, which earlier this year took a £1.4billion hit.

Songbird said high occupancy levels and its control over much of Canary Wharf - it owns about 60% of the 14 million sq ft estate - meant it was less exposed to weakness in the property market. However, it was quick to warn it was not immune to the slowdown.

Reporting a fall in profits from £884.1million to £182million, chairman David Pritchard said: "Weakness in global financial markets has forced a slowdown in activity in the UK commercial property market which has been reflected in a softening of real estate values. The group's property portfolio has not been immune. The challenging market conditions experienced in the second half of 2007 have continued into the first three months of 2008."

Songbird said it had abandoned all speculative projects - those where it builds before it has found a tenant - meaning its proposals for 25 Churchill Place and Riverside South will be prepared but not developed.

However, it insisted lettings by stricken investment bank Bear Stearns would be honoured by its buyer, JPMorgan Chase.

Pritchard reiterated his commitment to Crossrail, the key east-to-west rail link through London that will take thousands of workers to Canary Wharf every day. Analysts reckon the current Docklands workforce of 93,000 will expand to more than 150,000 in the next 10 years.

"Crossrail will form an important part of London's future infrastructure and future prosperity," he said.