Peter Robinson has accused Environment Minister Mark H Durkan of breaching his code of office by scrapping the Planning Bill.
Attorney General John Larkin also weighed into the dispute by saying that legal advice obtained by the SDLP Environment Minister was "mistaken".
Now it has emerged that Mr Robinson, Deputy First Minister Martin McGuinness and Mr Durkan are to hold talks on the issue in the near future.
It is understood officials from the DUP, Sinn Fein and Alliance met last week to attempt to chart a way forward, with the future of major projects including a John Lewis-led development at Sprucefield, outside Lisburn, hanging in the balance.
Mr Robinson was asked by his party colleague Peter Weir whether he believed Mr Durkan had broken his pledge of office.
Mr Robinson replied: "The Executive took a clear decision on the matters; it is recorded in the minutes of the Executive meeting.
"Therefore, yes, the Environment Minister is in breach of the pledge of office. However, without going into his position, it is important that we resolve the issue."
He castigated Mr Durkan for failing to discuss his plan to withdraw the Bill with Executive ministers before announcing it.
"It is still the case that many potential investors that we speak to throughout the world and who are looking to invest in Northern Ireland have been put off by our planning system," he went on.
There was no immediate response from Mr Durkan, who has argued the Bill as amended gives too much weight to economic concerns over environmental ones.
Mr Robinson added: "To me, the right thing to do would have been to put the legislation through the Assembly and allow it to be tested in the courts if necessary. I hope that we can reach some agreement on how we should go forward."
STORY SO FAR
Environment Minister Mark H Durkan dropped the Planning Bill after amendments – giving more weight in decisions to economic rather than environmental considerations – were passed in the Assembly. The amendments were introduced by Peter Robinson and Martin McGuinness after an 'economic pact' negotiated with Prime Minister David Cameron.