Rush-hour traffic is expected to grind to a halt this evening as taxi drivers take part in a "slow drive" across Sheffield.
Taxi drivers will stage the "slow drive" this afternoon in protest of new Government licensing legislation.
The protest is expected to start at 4pm with a convoy of taxis travelling from Attercliffe to the city centre.
Drivers will also protest outside the Town Hall at 1pm to protest the new rules which they say have created a "wild west" working environment.
GMB, the trade union for thousands of Hackney cab and private hire drivers, has organised the demonstration to oppose the Government's Deregulation Act.
The act allows private hire taxis licensed in one local authority area operating across the whole country.
This, the union says, has meant drivers registered in London and other areas are working in Sheffield.
GMB is also targeting Uber, which it says is not subject to the same checks as locally-registered driver.
Sheffield taxi driver and GMB rep Ibrar Hussain said: "Cross border hiring is killing our taxi trade.
"Government needs to act urgently as deregulation is putting public safety at risk, allowing Transport For London (TFL) to act with impunity and is restricting the powers of licensing authorities to enforce standards and safeguards."