The opposition leader, in Solomon Islands, Fred Fono, plans to put forward a motion of no confidence in the Prime Minister when parliament sits today.
Mr Fono said Mr Sogavare's actions in recent weeks have antagonised Australia, especially the expulsion of Canberra's ambassador Patrick Cole.
The opposition leader says support for the Prime Minister has dwindled and he now has the numbers to topple him.
The Deputy Mayor of the Solomon's capital, Honiara, has appealed to the people of the city to remain calm during this potential political upheaval.
The Australian high commission in Honiara has warned Australians in the Solomons to take extra precautions.