The Oilfields Workers Trade Union (OWTU) has delivered a letter to the Office of the President, outlining its position with regard to the decision to close the Petrotrin refinery.
President Paula-Mae Weekes is currently out of the country and Senate President Christine Kangaloo is acting as President of the Republic.
The OWTU leader, Ancel Roget is calling for an inquiry and public debate into the decision.
He will also deliver letters to the Leader of the Opposition, Kamla Persad-Bissessar and Independent Senators during the course of the day, as part of what Roget calls their "campaign of awareness".
He said the contents of the letter delivered this morning will be made public after the president has time to peruse the document.
Roget is again denying reports that he knew the government was going to shut down the refinery.
"In all deliberations we would have had, there was never any categorical decision on shutting the refinery down," he said.
He said what the union interpreted from the meeting was that a decision was being taken to sell the refinery.
Roget said the OWTU had seven members in the meeting and none of them got the interpretation that the refinery was to be shut down.
He says an inquiry will determine who are experts that helped the government make the decision, and what was the basis of giving this decision.