WATCH: Behind the scenes in the COP26 conference 'Blue Zone' at the SEC in Glasgow

The Clydeside complex, which includes the distinctively-shaped Armadillo and Hydro concert venues, has been significantly expanded with a series of interlinked temporary buildings on the site.

Delegates were today passing through a series of security checkpoints before they could enter the site to register, where they also had to show evidence of a negative Covid test.

Once the United Nations event gets underway on Sunday, arrivals will be funnelled through a special security hall, which has a separate “ministerial entrance”.

The COP26 registration hall. Picture: The Scotsman

Other temporary buildings include a vast registration hall with adjoining large cloakroom area, beside the Hydro.

Footage from a video filmed by The Scotsman showed work still underway on connecting corridors between various auditoria, and the main arenas at the Armadillo and Hydro being kitted out with seating, speaking platforms and floral decorations.

Plenary sessions of the conference will be held in halls in the main SEC building.

The Blue Zone extends for a mile west as far as the Riverside Museum, including a vehicle security check area.

The main entrance to the COP26 conference from Sunday. left, with the "ministerial entrance" beside it. Picture: The Scotsman

More than 20,000 delegates are expected to attend the event, and gets properly underway on Monday, when some 120 world leaders and their delegations are due to take part.

A fleet of some 240 electric Jaguar Land Rover cars will ferry heads of state to the conference, with more than 50 expected to be staying in Edinburgh because of the proximity of their consulates for secure communications.