The union federations, of which the SoR is a member, warn the decision will threaten the peace process in Northern Ireland and lead to a potentially damaging trade war.
Commenting on the new legislation, TUC general secretary Frances O’Grady said:
"It says everything about ministers’ warped priorities that in the middle of a cost-of-living emergency, they announce legislation that could provoke a trade war and cause prices to skyrocket further. Working people must not pay the price for this reckless move.
"The government must drop this bill, honour the agreement they signed up to and put practical solutions ahead of posturing. Ministers need to get back around the table with the EU as soon as possible and come to an agreement that protects jobs, rights and the Good Friday Agreement. The government must show that it respects international agreements to repair its now-trashed reputation as a trading partner."
Assistant General Secretary of The Irish Congress of Trade Unions, which represents trade union members in Northern Ireland and in the Republic of Ireland, Owen Reidy said he recognised there were "practical issues" when negotiating a post-Brexit trading agreement and that these must be addressed.
"However, the only credible way to do this is for the UK government to start to engage with the EU in good faith, as opposed to taking unilateral action which makes an agreement on the implementation of any protocol more challenging and difficult."