The Cook Islands Party claims the Democratic Party government may have diverted money from a local industry to buy tractors for election bribes.
The Ministry of Agriculture says the 25 tractors valued at 1.2 million US dollars were donated by the Chinese Government.
But Cook Islands Party leader Henry Puna says the tractors may breach the electoral act which states that anything given to influence the way a person votes constitutes bribery.
Mr Puna says sources from the Ministry of Finance have told him that 2 million dollars of Chinese funding the government had pledged to the black pearl industry in the Manihiki constituency was diverted to pay for the tractors.
"There is a very strong suspicion as to why the money was diverted from Manihiki, one constituency, to buying these tractors, which will be dished out as the government says, one for each of the 24 constituencies in the Cook Islands."
Henry Puna is questioning the timing of the tractors' distribution three weeks before the election.