The internet giant decided earlier this year not to take office space at Oxford House.

That delayed the construction schedule which has been put back again while the developer mulls over its plans.

Great Portland Estates said: “At Oxford House, 76 Oxford Street, W1, we achieved planning approval in June 2016 for a 89,100 sq ft major mixed-use refurbishment.

“Facebook had a right of first offer to take all of the 55,700 sq ft of office space which they chose not to exercise.

“We are now exploring whether a more substantial redevelopment, including improving the quality and scale of the retail space, would add additional value given the strong demand for high quality retail units at the eastern end of Oxford Street due to the opening of Crossrail in 2018.”

The developer’s other scheme in the near-term pipeline is at Hanover Square in west London where demolition is now complete.

The company said: “These limited works give us the option, should the market be supportive, to accelerate the construction programme for the wider scheme ahead of delivery of the station structure by Crossrail in 2018.”

Great Portland estates said it has 12 uncommitted schemes in the pipeline for the next property cycle totaling 1.3m sq ft.