Keir Starmer laid flowers for the children killed in the Southport knife attack … before meeting prominent Labour pals for drinks in Downing Street's rose garden

As the Mail on Sunday revealed, just hours after laying flowers for the children murdered in the knife attack in Southport, Sir Keir Starmer attended a party in the garden of Downing Street with prominent Labour supporters.

The Prime Minister mingled with Labour supporters at a barbecue at No. 10 on the evening of July 30, after laying flowers earlier that day in Southport, where three children were stabbed to death during a dance lesson.

Celebrity guests at the event included television presenter June Sarpong, soap opera actress Michelle Collins, and Helen Thorn and Ellie Gibson, who host the Scummy Mummies podcast.

As the MoS announced, the event was also attended by Labour donor Lord Waheed Alli, who has donated more than £900,000 to the party and its candidates since 2004.

According to the newspaper, Sir Keir arrived at the party in the Downing Street Rose Garden at around 8pm. About half an hour later, violence broke out in Southport, with hundreds attacking a mosque. Earlier, it was reported that Lord Alli, whose fortune is estimated at £200 million, had organised a post-election reception in the Downing Street garden with others who had funded the campaign.

Sir Keir watches the laying of flowers for three young girls who were killed in a knife attack during a Taylor Swift dance lesson.

The Prime Minister lays his own floral tribute in Southport

The Prime Minister's message reads: “To the victims, families and people of Southport, our hearts are broken. There are no words for such a profound loss. The thoughts of the nation are with you.” The message is signed by Keir Starmer.

Labour sources denied that Lord Alli organised, hosted or paid for the barbecue on 30 July – but acknowledged that he was among the party supporters in attendance.

Sir Keir faced accusations of hypocrisy last night after claiming last month that under the Tories the Rose Garden – where Boris Johnson was photographed eating cheese and drinking wine with staff during the first Covid lockdown – had “become a symbol of the rot at the heart of their government”.

Senior Tory MP Sir Alec Shelbrooke said: “Sir Keir is now exposed as a hypocrite of the worst kind.”

“The only flaw here is that Sir Keir's behaviour in government stands in woeful contrast to his pious, hypocritical words.”

Reform MP Richard Tice said the party showed “an incredible lack of empathy, sympathy and awareness of the state of the country”.

According to sources, the barbecue, which was scheduled to take place between 5:30 p.m. and 7:30 p.m., was intended to thank volunteers and activists for their hard work and support during the election campaign.

More than 100 guests were served sausages and rosé wine and Deputy Prime Minister Angela Rayner gave a speech before Sir Keir arrived.

Ms Sarpong, a former girlfriend of Foreign Secretary David Lammy, posed for a photograph with Larry, the Downing Street cat, outside Number 10.

“After 14 VERY long years, it's good to be back in 10 Downing Street and have a Labour Prime Minister there!” she later wrote on Instagram.

Ellie Gibson (left) and Helen Thorn (right), who present the Scummy Mummies podcast, were present in Downing Street

Sir Keir walks through the rose garden in Downing Street. After Boris Johnson was photographed sipping wine and cheese in the garden during the Covid lockdown, Sir Keir called it “a symbol of the rot at the heart of your government”.

Senior Tory MP Sir Alec Shelbrooke (pictured right) said: “Sir Keir is now exposed as a hypocrite of the worst kind”

Reform MP Richard Tice (pictured) said the party showed “an incredible lack of empathy, sympathy and awareness of the state of the country”.

Mrs Sarpong, a former girlfriend of Foreign Secretary David Lammy, posed for a photograph with Larry, the Downing Street cat, outside No. 10

Home Secretary Yvette Cooper walks with flowers near the scene where three children were killed in Southport

Mrs Cooper (pictured laying a bouquet) made a somber statement to the House of Commons, informing MPs of the “devastating attack” in Southport and naming the three victims who died

Just before 6.30pm, while the barbecue was still in progress, Home Secretary Yvette Cooper made a grim statement to the House of Commons, informing MPs of the “devastating attack” in Southport and giving the names of the three people who died.

Earlier, Sir Keir was booed in the coastal town as he delivered his condolences, with one man declaring: “Here's your photo opportunity.”

A Labour source said: “The Tories celebrated drunkenly and puked on the walls while the country played by the rules.”

“The Rose Garden is now back in use and has been used to thank people across the country who gave everything to help Labour win.”