David Cameron has rejected fresh calls to ban all zero-hours contracts amid anger over Sports Direct boss Mike Ashley's admission he paid workers below the minimum wage.
Jeremy Corbyn described Mr Ashley as a boss who "would make Scrooge look like a good employer" and called for an outright ban on zero-hours contracts, which many Sports Direct employees are on.
The Prime Minister insisted some workers want to have the choice of a zero-hours contract and stressed he had already banned those which tie employees to one company exclusively.
Mr Corbyn said he had met workers and discussed the "shocking behaviour" at Sports Direct, including "non-payment of the minimum wage, a culture of intimidation and fear, on top of the insecurity and exploitation of zero-hours contracts".
At Prime Minister's Questions, the Labour leader added: "Will you do what some other European countries have done and ban exploitative zero-hours contracts here?"
Mr Cameron replied: "On the issue of Sports Direct and the appalling practice of not paying the minimum wage - I absolutely abhor it and this Government has done more than any previous government to crack down on the non-payment.
"We have levied almost 5,000 penalties since 2010, we continue to name and shame eligible employers when the investigation has been closed, something that didn't happen before.
"Penalties for not paying the minimum wage are at a record high and the total value of penalties last year was over 15 times bigger than in 2010.
"So, on top of our national living wage we are going after unscrupulous employers and making sure that people get the deal that they deserve.
"On the issue of zero-hours contracts - we legislated in the last parliament to stop exclusive zero-hours contracts but we followed the conclusions of our consultation that said that we shouldn't go further than that, and that for some people they want to have the choice of those contracts."
Mr Corbyn said working practices at the retailer showed the Government needs to strengthen employees' rights as he turned to the EU referendum.
"The case of Sports Direct shows that Mike Ashley certainly isn't a Father Christmas, indeed he would make Scrooge look like a good employer," the Labour leader said.
"I think we should commend Unite the union and its members for exposing what went on and it shows that we must strengthen, not weaken, workers' rights, particularly when there's criminal activities involved."
Mr Corbyn warned that many of the Government's leading ministers are campaigning for Brexit on a platform of weakening workers' rights.
He highlighted comments from employment minister Priti Patel about reducing the "burden" of EU employment legislation and Michael Gove's admission that jobs may be lost in the event of Brexit.
The Labour leader said: "If it is a modern, compassionate Conservative Government as you describe it, why does it have an employment minister who wants to reduce the burdens, as she describes them, of employment legislation and make work less secure?
"Could I quote one other person who's given some opinions on these matters?
"He says 'I can't guarantee every person currently in their current job will keep their job' - that was Michael Gove who is the Justice (Secretary), who seems equally relaxed about unemployment rights.
"So you have an employment minister and a justice minister who want to reduce what they describe as workers' protection as a burden - can you do something about that?"
Mr Cameron insisted the ministers' views were personal and said the Government wants to remain in the EU and protect workers' rights.
The PM said: "As you know, we're holding a referendum, that is what is happening, the Government has a very clear position, which is we're stronger, safer and better off inside a European Union, that is the advice we're giving to voters in our country.
"But of course there are ministers in the Government who in a personal capacity are campaigning on another side of the argument.
"Now I don't agree with them, so I don't agree with what Mr Gove said, I don't agree with what Ms Patel said, and I couldn't be clearer about that - the Government has a clear position."
Meanwhile, Mr Cameron used the theatre of PMQs to bring out cross-party cheers around the Commons for Britain's EU membership.
Gesturing around the chamber at MPs from different parties, he said: "And on this issue not only do you and I agree, not only does the Conservative Government and the Labour Party agree, but we also have the support of the Liberal Democrats, we have the support of the Ulster Unionist Party, we have the support of the Green Party.
"This is one occasion when business large and small and trade unions are on the same side and I think we should celebrate that and get out and campaign as hard as we can."