Nigel French PA Archive/PA Images
Labour leader Jeremy Corbyn has repeatedly claimed that the government plans to turn Britain into a "bargain basement economy" with "low wages and worse conditions."
However Khan today dismissed the claims, saying that he had seen "no evidence" that ministers wanted to erode rights.
"There has been some anxiety about comments made that we would become a 'offshore tax haven'" Khan told the London Assembly.
"Because the implication is that would lead to a dilution of workers' rights. I have seen no evidence from the conversations I have had with senior members of government that this is their aspirations, their intentions or what they want to do."
He added that he was hopeful that the current level of rights for employees would be a "floor rather than a ceiling" post-Brexit.
Khan told AMs that he had taken part in regular monthly meetings with Brexit Minister David Davis where he was afforded an "open discussion" about Brexit.
"I give David Davis and the government credit for not ignoring the needs of London," he said.
Khan's comments are the latest disagreement between the Labour London mayor and Corbyn. Khan has been a vocal critic of the Labour leader on issues including national security and the monarchy.
Khan did initially nominate Corbyn to stand for leader in 2015 but voted for Andy Burnham instead. He later urged Labour members to back Owen Smith in the subsequent Labour leadership election last year.
Khan's name was booed by hundreds of Corbyn's supporters when it was mentioned during one of his rallies last year.
We cannot let @Theresa_May use Brexit to turn Britain into a tax haven on the edge of Europe and create a bargain basement economy. #Brexit pic.twitter.com/QmKCtr0vtC
- Jeremy Corbyn MP (@jeremycorbyn) January 17, 2017