Wealthy clients and oligarchs from autocratic countries are using prestigious London law firms to intimidate and silence journalists, MPs have said.

A cross-party group of MPs has called on ministers to introduce legislation to stop deep-pocketed individuals and powerful corporations from misusing the justice system to “intimidate and destroy” journalists.

Speaking during a debate in the House of Commons on Thursday, MPs urged the government to better protect the media and citizens from abusive legal actions known as strategic public participation lawsuits, or Slapps .

Lawyers and activists describe Slapps as a form of legal harassment that exploits lengthy and costly legal proceedings to silence journalists, critics and watchdogs.

David Davis, a Tory MP and former Cabinet minister, said ‘vile’ actors were using the justice system ‘to threaten, intimidate and make UK journalists, citizens, civil servants and media organizations fear God’.

Davis called such tactics “lawfare” and cited recent examples where journalists had faced “reputational and financial ruin in defending themselves from these malicious cases.”

MPs drew particular attention to the work of a series of elite English law firms specializing in media litigation.

Davis said: “It’s very clear that some London-based law firms have found an incredibly profitable niche that they’re willing to pursue without worrying too much about the outcome. I think the professional bodies of these law firms should look at them very closely, as should the government.

Another Tory MP, Bob Seely, said the UK had a “law cottage industry”. He said: “If we allow the cancer of the sale of bullying services by high-end law firms, it will do us no good in the long run, just like in the long run, letting the mafias launder money would also be bad for us.”

He added: “We need to pass anti-Slapp legislation, and we need to prosecute these lawyers – dare I call them slappers – who use such tactics.”

MEPs highlighted recent cases brought against investigative journalists, including Financial Times journalist Tom Burgis, who is the subject of defamation actions brought by Kazakh mining company ENRC, and Catherine Belton, the author of a recent book about Vladimir Putin, who faced a barrage of defamation lawsuits last year from several Russian billionaires and the state-controlled oil company Rosneft.

Two MPs, Seely and Liam Byrne from Labour, criticized English companies such as Mishcon de Reya, Schillings, Harbottle & Lewis, CMS and Carter-Ruck.

Sir Robert Neill, who chairs the Commons Justice Select Committee, said he hoped ministers would consider anti-Slapp legislation, but told MPs that “there are very important regulations relating to the conduct of cabinets lawyers in the UK”.

“We should not distort the position by saying that there is a high level of cynicism in the legal profession; there isn’t, and I don’t believe there is regulatory failure either,” he added.

Responding to the debate, Justice Minister James Cartlidge agreed that Slapps’ actions “represent an abuse of the legal system”, but said the government “must be careful to respond to Slapps in a proportionate way that perpetuates our tradition of balancing individual rights with the public good.

Reached for comment, a spokesperson for Mishcon de Reya said any suggestion that the company was involved in Slapps or other oppressive or intimidating litigation would be misguided and defamatory. Schillings, CMS, Harbottle & Lewis and Carter-Ruck did not respond to a request for comment.