Labour peers are to step up their campaign to stop the “reckless” Northern Ireland protocol bill being passed with demands for more than 20 changes. Jenny Chapman, the shadow cabinet minister in the Lords, told the Guardian the bill was “an abomination, undermining the UK’s hard-won reputation as a responsible, trustworthy partner” and called on the government to “scrap this reckless legislation”. When the committee stage begins in the Lords on Tuesday, Labour peers will put the government on notice that the bill will not proceed to the next stage until a variety of conditions are met. These include a promise that diplomatic efforts to end the row over the protocol are given a chance to work before any legislation is passed. The bill is one of Liz Truss’s flagship policies. In a motion of regret, Labour will also ask the government to prepare and publish “an impact assessment outlining the likely consequences of the use of powers in this bill on the Northern Ireland business community”. The party wants the government to publish “indicative regulations, which may be laid using the powers in this bill”, as well. The bill as it stands gives ministers powers to introduce new laws to undo Brexit arrangements with little scrutiny, something that has fuelled sharp criticism both in the Commons and the Lords. The proposed legislation has also been criticised on the grounds it would breach the international treaty signed by the EU and the UK agreeing to the protocol as a means of preventing a trade border with customs posts and checks between Northern Ireland and the Republic. Lady Chapman said: “The government must not squander the opportunity of its negotiations with the EU. With hard work and compromise on all sides, a deal is achievable to end this damaging, self-inflicted standoff, and scrap this reckless legislation.” Labour will table 22 “probing amendments” including several that would set strict conditions under which any laws could be used. The party is suggesting the proposed legislation should make it “a statutory requirement for the government to seek a negotiated outcome with the EU and to exhaust legal routes under the EU withdrawal agreement before availing itself of the powers in this bill”. Several amendments address fears raised by legal experts of the extraordinary powers the bill confers on ministers to create new laws. The government has claimed these powers are designed to undo EU rules on VAT and state aid but experts have said they would set a precedent that is dangerous in a democracy. The controversial bill was tabled by Truss earlier this summer when she was foreign secretary, but when she became prime minister she agreed to give negotiations another chance. In the last two weeks there has been a flurry of diplomatic activity involving talks between the foreign secretary, James Cleverly, and European commissioner and vice-president Maroš Šefčovič. The Northern Ireland secretary, Chris Heaton-Harris, has also said he hoped for a diplomatic solution that would make the need for the legislation “redundant”.