The Solomon Islands prime minister, Manasseh Sogavare, remains confident his leadership is not under threat.
The opposition leader, Fred Fono, has filed a motion of no confidence with the clerk of parliament, which is to debate it when the house sits next month.
While claiming to have substantial support, Mr Fono has declined to give details.
Local media reports say the move comes amid controversial decisions made by the Prime Minister.
Sam Alasia, the special advisor to Mr Sogavare, says the PM is not worried.
"In the past it's sort of a normal check and balance that has been experienced and normally when a new government a motion of no confidence will be moved within the first year, but at this point in time it comes just after six months."
The special advisor to the Solomons Prime Minister, Sam Alasia.
Parliament meets on October the second