An executive decree on the partial transfer of army units and budget to a royal security command unit sailed through the Senate yesterday with no resistance.
The Senate passed the decree by 223-0 votes after the House of Representatives on Thursday passed it by 374-70.
The MPs who voted against the decree were all members of the 81-strong opposition Future Forward Party (FFP).
The decree provides for the transfer of some manpower and part of the budgetary allocation to the 1st Infantry Regiment of the Ratcha Wallop Royal Guards and the 11th Infantry Regiment of the Ratcha Wallop Royal Guards to the royal security command unit.
The FFP argued on Thursday that use of an executive decree for a "non-urgent" matter was a case of the cabinet misusing its power in violation of the constitution.
Senator Somchai Sawaengkarn took to the floor to accuse the FFP of stirring conflict in the country. He defended the urgency of the decree, saying it was a matter of national security.
Mr Somchai called for an end to what he described as the party's "anti-royalist stance", saying it could lead to a crisis in the country.
The Senate will send the decree to Prime Minister Prayut Chan-o-cha, who will forward it to His Majesty the King for royal endorsement.