International architecture studios including Adjaye Associates, Morphosis, Studio Fuksas and Coop Himmelb(l)au have been named in a Riyadh exhibition as working on The Line megacity in Saudi Arabia.

Currently under construction in Saudi Arabia, the 170-kilometre-long megacity is being designed by numerous international studios, with each practice reportedly working on a 500-metre section.

Coop Himmelb(l)au, Peter Cook and Studio Fuksas also among the architects named

Twelve architecture studios are named in The Line Exhibition, which is currently on display in Riyadh, Saudi Arabia, according to reporting by Architects' Journal.

US architecture firm Morphosis, which is led by Pritzker Architecture Prize-winning architect Thom Mayne, has been long rumoured to be leading the design. The studio declined to comment when asked about its involvement by Dezeen.

Alongside Morphosis, 11 other studios were named in the exhibition as being involved in the project.

These studios are US practices Pei Cobb Freed & Partners, Tom Wiscombe Architecture, Oyler Wu Collaborative and HOK; UK studios Adjaye Associates and Peter Cook's studio CHAP; Austria studios Coop Himmelb(l)au and Delugan Meissl Associated Architects; Italian practice Studio Fuksas; and Dutch studios UNStudio and OMA.

However, representatives for OMA and UNStudio told Dezeen that the studios are not working on the project but did participate in a design competition in its early stages.

The extent of the other studios' involvement in the project is unclear.

Dezeen has contacted Adjaye Associates, Pei Cobb Freed & Partners, Oyler Wu Collaborative, CHAP, Delugan Meissl Associated Architects, UNStudio and Studio Fuksas for comment. HOK declined to comment.

Unveiled last year, The Line is being designed to house nine million people. It will stretch 170 kilometres across the Neom region of southwest Saudi Arabia but will be just 200 metres wide, enclosed with 500-metre-tall mirrored facades.

Neom criticised for human rights and sustainability

The project has been widely criticised for its sustainability and liveability claims. There have also been reports of human rights violations attached to the project with human rights organisation ALQST reporting that three men who had been forcibly evicted from the Neom site had been sentenced to death.

Speaking to Dezeen in an exclusive interview, Neom's executive director for urban planning Tarek Qaddumi defended the project saying that it will "revolutionise our current way of life" and will be net-zero over its lifetime.

The Line forms one element of the wider Neom project, which will contain 10 regions when it is complete. Alongside The Line, an octagonal floating port city and a resort island designed by architecture studio Luca Dini Design and Architecture are planned.

A ski resort being designed by UNStudio, UK studio Zaha Hadid Architects, US studio Aedas, German studio LAVA and Australian studio Bureau Proberts will also form part of the project.

This article was amended to reflect the fact that UNStudio confirmed it was not currently working on The Line.