Rem Koolhaas and OMA’s plans to renovate the largest museum building in Russia have been unveiled.

The New Tretyakov Gallery houses an extensive and important collection of Russian art, including work from Malevich, Kandinsky, Chagall, and Soviet artists such as Aleksandr Deyneka and Vera Mukhina.

The 61,000sq m (657,600sq ft) building, which includes multiple exhibition halls, was originally designed by architects N.P. Sukoyan and Y.N. Sheverdyaev in the 1960s, and took two decades to complete. Several additions that have been added over time, fragmenting the vast hallways and grand exhibition spaces into clusters of smaller rooms.

OMA’s redesign will create four sectors – art storage, an education centre, the collection galleries, and a festival hall – each with a distinctive identity and role. These wil be linked by a new pedestrian route along Moscow River, with cutouts in the museum’s façade opening up its interior spaces to the city.

“Our proposal is a reconsideration of the New Tretyakov, focusing on improving its spatial infrastructure and the elimination of dysfunctional parts,” said Koolhaas. “We also remove a number of walls to make the different components more accessible and visible. Because of its size, it is almost impossible to consider it as a homogeneous entity; modern interventions unaffordable in Soviet times, such as escalators, improve circulation and draw together the different autonomous elements of the museum complex.”

Local architecture firm Reserve will collaborate on the project.

OMA's previous large-scale cultural projects include the Fondazione Prada in Milan, the Design Museum in London and the newly-opened arts space Concrete in Dubai.

They are currently working on an expansion of New York's New Museum, the Factory cultural venue in Manchester and a striking theatre in Taipei.