By David Hunter
The heads of Northern Ireland's two main parties have written to the US Vice president over the Bombardier Jobs dispute.
Hundreds of positions could be at risk in a Belfast factory which makes wings for the C-Series aircraft.
Boeing has complained to the US Government that a deal to supply planes to fellow American airline, Delta, was unfairly subsidised by the Canadian and British governments.
The US Department of Commerce will rule on the complaint later this month.
It's also emerged today that Prime Minister, Theresa May, will meet her Canadian Counterpart, Justin Trudeau over the issue later this month.
In a letter to the American Vice President, Mike Pence, Arlene Foster and Michelle O'Neill said they wanted assistance addressing "A very grave economic threat" to the region.
The letter said: "For a small economy such as ours, the significance of the contribution that bombardier makes cannot be understated. The threat facing us all as a result of this ongoing case is alarming, and goes much wider than it may immediately appear.
"The security of our economy has and continues to be a crucial part of our efforts in delivering peace through prosperity. At a time when we are striving to take the next steps in our work on the peace process, and resolve our current political difficulties, this issue creates a new and potentially critical factor."
A copy of the letter was also sent to senior staff in Boeing, the Prime Minister and the British Secretaries of State for Northern Ireland, Business and defence.
In signing off the political leaders reflected on the long term economic ties between Northern Ireland and the states.
It read " The United States has been our friend and ally for many years. Your long term friendship has been of incalculable value in helping deliver peace and prosperity.
"At this crucial and sensitive time for the future we would ask that you give consideration to the implications any decision may have here."