Vanuatu's Council of Ministers has reiterated that it won't accept the appointment of the Fijian Amena Yauvoli as new director-general of the Melanesian Spearhead Group.
Mr Yauvoli's selection to the position was confirmed last week by the MSG chairman, Solomon Islands prime minister Manasseh Sogavare.
However, Vanuatu's prime minister Charlot Salwai objected, saying the appointment was to have been settled at next month's MSG leaders summit in Port Vila.
Mr Sogavare subsequently denied Vanuatu's claim that the appointment had been made outside of MSG rules.
He said that following the sudden resignation of Peter Forau as MSG director-general last year, it was a matter of urgency to appoint someone to the position in the interests of the secretariat being able to function effectively.
However, an announcement by Fiji's government earlier in the month that its diplomat was to be the new head of the MSG secretariat came as a surprise to Vanuatu's government.
Vanuatu's government planned to nominate the country's ambassador to the European union, Roy Mickey-Joy, for the position.
It now says Mr Mickey-Joy and the other applicants who applied for the position of DG of the MSG can seek judicial review of the appointment decision announced by the chairman.
West Papua issue
The decision by Vanuatu's government to stand firm on the director-general appointment issue comes in close proximity to the West Papua issue.
The Council of Ministers has also instructed the government to propose at the upcoming summit that the United Liberation Movement for West Papua become a full member of the MSG.
The Liberation Movement was granted observer status in the MSG last year, as Indonesia was also elevated to associate member status.
Vanuatu has now confirmed that at the summit it will also push for Indonesia to no longer be an associate member of the MSG.
Jakarta is opposed to the Liberation Movement representing the indigenous people of its Papuan region politically, and has been lobbying other Melanesian countries to counter the Movement's large public support in the region.
After his recent tour to the Pacific region, Indonesia's minister for Political, Legal and Security Affairs, Luhut Binsar Pandjaitan, said Jakarta had won the backing of Fiji and Papua New Guinea for its push to be a full member.
It was on the heels of Luhut's visit to Suva that Fiji's foreign minister Ratu Inoke Kubuabola "announced" that his government's candidate for MSG director-general had been selected for the role.
It's clear the issue of West Papuan involvement in the MSG remains divisive in the group
The Vanuatu government has long been the staunchest supporter of West Papuan self-determination rights, which has at times pitted it against other MSG members, notably PNG and Fiji.
However, Vanuatu's disagreement with the Solomon Islands leader over the director-general appointment adds another dimension to this emerging standoff.
The MSG leaders summit is expected to begin on 6 May in the Vanuatu capital.