Fiji's opposition leader, Mick Beddoes, says the president has signalled a vote of no confidence in the government by rejecting its inquiry into the army commander.
He says questions are being raised as to why Ratu Josefa Iloilo gave his initial approval to the inquiry but then changed his mind.
The government proposed holding the inquiry after suspended army officers alleged that Commodore Frank Bainimarama planned to overthrow it.
Mr Beddoes says he's never supported the idea but people now want to know what's going on.
"The president should explain the reason behind his decision not to proceed, having already granted approval, initial approval, to the government. Certainly if one looked at it from a purely political basis, this almost is equivalent to a no confidence vote from the president in his government."
Mr Beddoes says there should be an inquiry into the 2000 coup.