Vanuatu's ousted prime minister, Edward Natapei, says a motion of no confidence is likely to be lodged this week to challenge the new prime minister, Serge Vohor.
This comes after last week's victory of Mr Vohor's coalition in the newly elected 52-seat parliament in which he had the support of 28 members.
But Mr Natapei of the opposition Vanuaaku Party says some MPs from the ruling coalition have defected reportedly after failing to get ministerial posts they were promised.
"It is clear from the way the government was set up that a lot of the members were lied to and kept in a camp against their wishes. So soon after the formation of the government they decided to come across to our side and change the balance of the numbers."
Edward Natapei .
Meanwhlile, the indigenous enterprise minister, Arnold Prasad of the Greens, has resigned after failing to get the agriculture portfolio as promised.
