As he closes in on the Republican presidential nomination, former President Donald Trump made a highly unusual stop, hawking new Trump-branded sneakers at Sneaker Con, a gathering that bills itself as the “The Greatest Sneaker Show on Earth”.

Trump was met with loud boos as well as cheers at the Philadelphia Convention Centre as he introduced what he called the first official Trump footwear.

The shoes, gold lame high tops with an American flag detail on the back, are being sold as “Never Surrender High-Tops” for US$399 ($650) on a new website that also sells Trump-branded “Victory47″ cologne and perfume for US$99 a bottle. He would be the 47th president if elected again.

The website says it has no connection to Trump’s campaign, though Trump campaign officials promoted the appearance in online posts.

On Friday, a judge in New York ordered Trump to pay a whopping US$355m in penalties, finding that the former president lied about his wealth for years, scheming to dupe banks, insurers and others by inflating his wealth on financial statements.

That penalty came after Trump was ordered to pay US$83.3m to the writer E. Jean Carroll for damaging her reputation after she accused him of sexual assault. With interest payments, Trump’s legal debts might now exceed half a billion US dollars - an amount it is unclear he can afford to pay.

Trump’s appearance was met with clashing boos from his detractors and chants of “USA!” from supporters who arrived at the sneaker event decked out in Trump gear. The duelling chants made it difficult, at times, to hear Trump speak. Some held signs that read “SNEAKERHEADS LOVE TRUMP.”

Donald Trump holds gold Trump sneakers at Sneaker Con Philadelphia, an event popular among sneaker collectors. Photo / AP

“There’s a lot of emotion in this room,” Trump said of the reaction, after holding up and showing off a pair of gold shoes, then placing one on each side of his podium.

“This is something that I’ve been talking about for 12 years, 13 years,” he said.

• Judge orders Trump to pay US$364m in New York civil fraud case
• 'More experienced': Putin says he prefers Joe Biden over Donald Trump
• 'Stakes could not be higher': 2024 US presidential primaries explained

As he spoke, the smell of weed occasionally wafted through the room.

Some of those who attended said they were unaware Trump would be there and continued to shop as a crowd gathered around the stage. Many in the audience said they were not from the city and instead hailed from nearby states and Washington.

The attendees skewed younger and more diverse than Trump’s usual rally crowds. Trump’s campaign is hoping he will be able to win over more young and minority voters, particularly young black men, in a likely rematch against President Joe Biden in November.

This isn’t the first money-making venture Trump has announced since launching his third campaign for the White House in 2022. Trump last year reported making between US$100,000 and US$1m for a series of digital trading cards that portrayed him, through photo editing, in a series of cartoon-like images, including an astronaut, a cowboy and a superhero.

Trump’s new sneaker website says it is run by CIC Ventures LLC, a company that Trump reported owning in his 2023 financial disclosure. A similarly named company, CIC Digital LLC, owns his digital trading card NFTs, or non-fungible tokens.

The website states the new venture “is not political and has nothing to do with any political campaign.”

A Trump spokesman did not respond to questions about the event, including whether Trump was paid to attend.

The website describes the shoes as a limited-edition, numbered “true collector’s item” that is “bold, gold, and tough, just like President Trump”.

“The Never Surrender sneakers are your rally cry in shoe form,” the description reads. “Lace up and step out ready to conquer.”

Among those in the crowd were Jonathen Santiago, 21, and Danea Mitchell, 20, Trump supporters who drove from Monroe County in the northeastern part of the state for the sneaker event. They said they were excited to see the former president and praised how he interacted with the crowd. They also had kind words for the sneakers.

“The red bottoms were a really nice touch,” Mitchell said.

She shrugged when asked about Trump’s legal troubles. “I think it’ll be an interesting four years if he’s found guilty, but I have no doubt he’ll be president,” she said.

Also in attendance was a group of “cheer moms” from New Jersey who said they were in town for a cheerleading event and decided to stop by for a chance to see Trump.

Karla Burke, 48, said she heard some people booing and making noise, but that most people around her had been supporters. “At the front was a different vibe,” she said.

As for Friday’s penalty in Trump’s civil fraud trial, Burke said it doesn’t change her support. “I think it was unfair,” she said. “They’re just going after him so he’s not the Republican candidate.”

Biden-Harris 2024 Communications Director Michael Tyler slammed the appearance, saying: “Donald Trump showing up to hawk bootleg Off-Whites is the closest he’ll get to any Air Force Ones ever again for the rest of his life.”

Trump planned a rally later today in Michigan, in the suburbs of Detroit.