BANGKOK » Three months after overthrowing Thailand’s last elected government, this Southeast Asian nation’s junta leader is stepping out of his army uniform for good — to take up the post of prime minister in a move critics say will only extend his time at the helm and consolidate the military’s grip on power.

Thailand’s junta-appointed legislature voted unanimously Thursday to name Gen. Prayuth Chan-ocha to the post during a session in Bangkok.

There was little doubt over the outcome since Prayuth was the only candidate.

The 60-year-old leader is due to retire from the army next month and the change appears aimed in part at keeping him at the helm as the military implements sweeping political reforms.

The vote was the latest in a series of moves by the junta to consolidate power on its own terms.

In July, the military adopted a temporary 48-article constitution, which allows Prayuth to hold the premiership while still in the military. Shortly afterward, the junta appointed the assembly that is dominated by active and retired duty officers.

Prayuth has effectively served as de facto premier since staging the May 22 coup.

His appointment must be officially endorsed by King Bhumibol Adulyadej, a formality likely to occur within a week.

Prayuth is then expected to name his Cabinet.