Campaigners fighting Sellar Property Group’s £775m Paddington Cube have been granted a hearing at the Court of Appeal in July.
SAVE Britain’s Heritage had an application for a judicial review against the controversial 14-storey building rejected last November.
However the group is appealing that decision and will have its appeal heard on 19 July.
The development will include 360,000 sq ft of office space, 80,000 sq ft of retail and restaurant accommodation over five levels, including a rooftop restaurant, access to Paddington Station and a £65m investment in a new Bakerloo line station and ticket hall.
Scaffolding has already started going up on the site and the entire area is expected to be scaffolded by the end of this month. Demolition is due to be completed by the end of this year with construction starting by March next year.
The proposed building, designed by Italian architect Renzo Piano, was initially granted planning permission in December 2016.
Then communities secretary Sajid Javid gave the green light for the plans in March last year, despite calls for a public inquiry into the project.
SAVE Britain’s Heritage has raised objections to the fact Mr Javid did not explain the reason for his decision.
SAVE Britain’s Heritage executive president Marcus Binney said: “The ability of the secretary of state to hold a public inquiry under an independent planning inspector is a vital safeguard, allowing contentious cases and issues to be examined and assessed in an open and public forum.
“An essential part of this process is that the secretary of state gives reasons when he declines to hold an inquiry.”
Sellar Property Group is developing the scheme in partnership with Great Western Developments.
Initial plans for the development involved building a 72-storey high-end residential building dubbed the ‘Paddington Pole’.
Irvine Sellar, the late chairman of Sellar Property Group, previously told Construction News the decision to convert the scheme from residential to office was partly because the high-end residential market had slowed.
The scheme is due to complete by the end of 2021.
Sellar Property Group declined to comment.