Wembley will host the Challenge Cup final on Saturday, 17 October, the Rugby Football League has confirmed.
Both semi-finals – Warrington v Salford and Leeds v Wigan – will be played behind closed doors at St Helens’ Totally Wicked Stadium on 3 October.
Those last-four ties, plus the final, will be shown live on BBC television.
Chief executive Ralph Rimmer said it was the Rugby Football League’s “fervent wish” to have fans at Wembley but added the decision “may be taken out of our hands”.
Cabinet office minister Michael Gove said on Tuesday that plans for fans to return to watch live sport events in England from 1 October will not go ahead.
This season’s Challenge Cup has been severely disrupted because of the impact of the coronavirus pandemic.
Super League club Toronto Wolfpack withdrew from all competitions in 2020 because of financial concerns, while the five clubs left in the cup from outside the top flight – whose league seasons had already been postponed – also pulled out.
That led to a restructured sixth-round draw, with six teams getting byes through to the last eight.
Rimmer said: “2020 has been a tough year for all for obvious reasons, but it is also a special one for rugby league (the sport’s 125th anniversary) and we have therefore remained determined to do everything possible to ensure a day of celebration as well as reflection at Wembley.”
“It has remained the fervent wish of the RFL that supporters of the two teams who reach the final would be able to join them there, as well as the thousands who bought tickets for Wembley before lockdown.”
“However, we recognise that public health must remain the priority, and these decisions may be taken out of our hands.”
Follow @sportrazzi12 on Twitter to stay updated with trending sport stories