The man, who was working for one of the scheme’s subcontractors, was taken to hospital on Wednesday and was released over the weekend.

This is the second worker to have been hospitalised, following an incident at the major commercial site near Victoria.

In April, a subcontractor was taken to a major trauma centre after a fall from height.

Land Securities and Mace issued a joint statement today confirming there had been an incident.

A spokeswoman said: “A subcontractor was involved in a fall at the site. We are fully cooperating with all the relevant authorities.”

An HSE investigation is now underway.

Mace started work on site in June 2013. The £380m project is due to complete in September.