UK Prime Minister Theresa May's visiting Northern Ireland on Tuesday as she seeks a Brexit deal that can avoid a border roadblock.
She'll tell business leaders a deal can be secured that can win a majority in Parliament as well as EU backing.
So far the European Union has insisted it will not renegotiate the already-agreed Irish border backstop solution in the Withdrawal Agreement.
But May needs to win changes to it to gain the backing of enough of her Conservative MPs.
Former US Senator George Mitchell - who was heavily involved in the Northern Ireland peace process - says all sides need to take care with the issue.