The Conservatives’ plan comes after Reform UK made similar pledges over the summer to take the UK out of the ECHR and deport 600,000 migrants within five years if it won power.
Badenoch sought to portray her party’s plans as more credible, adding that it was backed by “comprehensive legal analysis” in the form of a review by Tory peer and former justice minister Lord Wolfson of Tredegar.
“Reform have nothing but announcements that fall apart on arrival,” she added.
The Tory move to leave the ECHR creates a key dividing line with the Labour government, which has opted against leaving the treaty but is reviewing how it is applied in UK law.
Labour has also pledged tougher action to deal with small boat crossings over the English Channel, which are set to break record numbers this year.
Labour recently set out plans to lengthen refugees’ route to permanent settlement in the UK in a bid to make the country less appealing to migrants, and has negotiated a “one in, one out” pilot scheme with France.
Unlike Reform, the Tories are not promising to formally disapply the Refugee Convention, a 1951 treaty that prevents signatory countries from returning refugees to countries where they face serious threats to their life or freedom.
But the party says it would legislate to prevent courts having regard to it in asylum cases, with a pledge to leave if “activist judges attempt to override Parliament”.