Correction: In an earlier version of this post we mistakenly quoted Struan Robertson from Pinsent Mason - the views are now correctly attributed to Euan Lawson from Michael Simkins.

Lord Mandelson has committed the government to tough, French-style measures to warn suspected illegal file-sharers—but the ISPs that will have to eventually cut off the internet connection of the very worst offenders are protesting loudly and even threatening legal action.

TalkTalk’s executive director of strategy and regulation Andrew Heaney told Guardian.co.uk that if the government does move to disconnect users, the company would “would look to appeal the decision [to the courts] because it infringes human rights.” He says that if suspected offenders are treated as guilty until proven innocent, it would “substitute proper judicial process for a kangaroo court” and “lead to wrongful accusations.” The Carphone Warehouse-owned ISP is building a campaign through its dontdisconnect.us site, which urges users to sign petitions against the plans.

—The country’s biggest ISP BT (NYSE: BT) weighs in with its own statement of opposition: “BT remains concerned about some aspects of the Government’s proposals,” it says, adding that it too wants to know whether accused P2P offenders will have the right to a legal hearing. But more to BT’s dislike is that ISPs will bear some of the costs of Mandleson’s anti-piracy regime. “This could place a huge burden on the industry and force up broadband prices for customers,” it warns.

Two legal experts told us that the system would be legally sound in cutting off suspected offenders, if they given enough warning:

—Andrew Yeates, a media lawyer with Sheridans and a former director general of the BPI, said that the government would have to make sure the information given to consumers on what is legal is clear but said he expected a legal appeals procedure to be in place. “Lord Mandelson made it clear that they are expecting there to be an appeals process at the warnings so there will be protection for consumers, plus he hinted that at applying the technical procedures there would be a legal process.” He adds: “You have to remember: this is being done to stop illegal activities…”

—Struan Robertson, a technology lawyer with Pinsent Mason and the editor of Out-Law.com, Euan Lawson, a media lawyer with Michael Simkins LLP, echoed Vivendi (EPA: VIV) CEO Jean-Bernard Lévy’s comments in saying that P2P warnings are legally similar to traffic offenses, whereby defendants can plead guilty without being arrested or attending court. He suggests that piracy warnings might be worded similarly to letters sent to drivers suspected of speeding: “With speed camera letters, it’s asking you to confess that it was you—some people say it’s a forced confession,” he says. But he makes clear he backs the plans: “If copyright isn’t enforced then there’s no point in having the law.”

The European Parliament’s recently threw out the contentious amendment 138 of the forthcoming, wide-ranging telecoms package which would have guaranteed Europeans a hearing before disconnection, leaving the matter to member states to decide.

• UK Confirms Plans To Warn, Throttle, Kick Illegal Downloaders
• Euro-MPs Give Up Demand For Court Hearing Before ISP Disconnection