The Vanuatu Supreme Court is to decide whether signatures on blank paper can be counted as valid for a motion of no confidence.
The speaker, Philip Boedoro, ruled last week that the opposition's attempt to call a vote of no confidence, with the signatures of 28 signatures MPs, was not in order.
The government claims the signatures on the motion had been forged by the opposition.
MPs Daniel Toara, Arnold Prassad, John Amos and John Jonas each withdrew their signatures, claiming they were forged by the opposition.
The court heard that the signatures of the Minister of Climate Change, Tomas Larkin, and of Arnold Prassad were on two separate blank pieces of paper.
The opposition's lawyer, Garry Blake, argued that the signatures should be treated seriously and several opposition MPs say they personally secured the signatures and support of those MPs.