The mayor of Toronto has denied media allegations that he has been filmed smoking crack cocaine in a video secretly recorded by drug dealers.

Rob Ford, who was elected mayor in 2010, slammed claims by US website Gawker and newspaper Toronto Star as ridiculous and "absolutely not true."

"It's another Toronto Star [story]", the conservative mayor told reporters outside his home.

The scandal erupted when Gawker's editor John Cook and Toronto Star reporters Robyn Doolittle and Kevin Donovan claimed they had been separately offered the chance to buy a video purportedly showing Ford inhaling from what looks like a glass pipe while making erratic comments.

Star reporters said they were showed the 90-second video by "Somali men involved in the drug trade" who wanted six-figures sums for the tape.

"I'm f***ing rightwing," Ford appears to say at one point, the Star reported. "Everyone expects me to be rightwing. I'm just supposed to be this great ..."

In another segment he calls Canada's Liberal Leader Justin Trudeau "a fag" then looks at the person holding the recording mobile phone and says: "That better not be on."

The newspaper said it could not verify the authenticity of the video but it was clear that the person in it was Ford.

Ford's lawyer Dennis Morris said: I don't know whether or not such a video exists but I think it would be fair for the public to see such a video and make their own conclusions. I can tell you he denies the allegations."

"I have not seen any indication of him using any substances like this, or anything else for that matter," Ford's deputy, Doug Holyday, said.

"We all know videos can be altered and we certainly know drug dealers can't be trusted, so we don't really know what we're dealing with here and until we do I don't have much to say," Holyday said.

Crowd-funding campaigns to collect C$100,000 (£64,000) to purchase the video to make it public have been launched on website Indiegogo.