An organisation that campaigns against the creation of a hard border says it is considering a range of actions against the British government's UK Internal Market Bill, including a legal challenge.
The Border Communities Against Brexit group (BCAB) says it plans to step up its opposition to the proposals of British Prime Minister Boris Johnson in the next week.
Damian McGenity, one of the leading members of the organisation, said: "We thought some of the most sensitive questions had been settled in the Withdrawal Agreement made by the British government with the EU. But now Boris Johnson seems prepared to go back on his word."
He told RTÉ News that a "green wall of opposition" involving influential voices in mainland Europe, the US and Ireland, north and south, will be required to prevent the British government backing away from what was an international agreement.
Mr McGenity also confirmed that the BCAB group will shortly be erecting a new series of billboards along major roads with a blunt message about British government plans.
He said the organisation is considering a range of options in its renewed campaign, including the possibility of mounting a legal challenge to the British government's proposals.
In the past the BCAB staged a number of demonstrations in border areas and organised a number of public events.
It also held a rally at Stormont, urging Northern Ireland's politicians to play their part in the prevention of a hard border.