The Solomon Islands Finance Minister, Gordon Darcy Lilo, is reported to have left the government.
This comes ahead of tomorrow's parliamentary vote of no-confidence against Prime Minister Danny Philip whose government appears to be collapsing.
Three government ministers reportedly resigned on Wednesday and a further government MP has announced his defection.
The Opposition leader Dr Derek Sikua has told local media they have the backing of at least 31 of the country's 49 MPs.
Journalist Ednal Palmer of the Solomon Star says the government is understood to have sacked Mr Lilo.
"We're still to talk to the government to see on what grounds but he was confirmed to be with the opposition this afternoon and we saw him the opposition camp already, and someone in the government called and said Lilo has been fired."