Southwark Council has raised the Millwall FC flag above its Tooley Street headquarters as the club prepares to take on Wigan in the FA Cup semi-final at Wembley.
Council leader Cllr Peter John and chief executive Eleanor Kelly welcomed Millwall captain Paul Robinson and chief executive Andy Ambler to the council HQ in Tooley Street on Thursday.
Together they raised the Millwall flag to mark the club's achievement in reaching the semi-final of the world's longest running football tournament.
They were joined by young people who have benefited from Millwall's community projects, and club mascot Zampa the Lion.
Millwall will take on Wigan at Wembley this Saturday, while Chelsea play Manchester City the following day. The two winning teams will face each other in the final on 11 May.
Although Millwall's ground at the New Den is in the borough of Lewisham, the club has strong links with Southwark.
"Southwark is proud to be the spiritual home of Millwall FC, and many of our residents are lifelong supporters of the club," said Cllr Peter John.
"Flying the Millwall flag is our way of showing our support. Their fantastic achievement in reaching the semi-finals of the FA Cup is something we can all enjoy, and there will be a real buzz of excitement across Southwark on Saturday.
"I will be at the match cheering them all the way to the final, and I'm sure they will feel the support of the borough behind them as they take on Wigan."
Millwall captain Paul Robinson said: "It's fantastic to be part of an event like this. The players and staff are grateful to Southwark Council for marking this occasion and for recognising Millwall's good work in the community, which often goes unnoticed."