The coalition has marked one year in government with significantly less support than when it came to power, the latest Newspoll shows.

The poll, published in The Australian newspaper on Tuesday, also reveals one in four voters don't want Tony Abbott or Bill Shorten as prime minister, and would give their first preference to the Greens, independents or a minor party.

The coalition's primary vote has dropped to 39 per cent, more than six points lower than the 45.6 per cent election result.

The ALP's primary vote is lower than the coalition's at 35 per cent, but Labor leads in two-party-preferred terms by 52 to 48 per cent.

Meanwhile, a separate Newspoll shows three out of five Australians are in favour of the federal government providing humanitarian aid and weapons to forces opposing Islamic State militants.

Conducted at the weekend and also published in The Australian, the poll of 1207 people revealed that 62 per cent of voters supported the action taken so far by the Abbott government, which has involved humanitarian aid drops, as well as shipments of weapons and ammunition.

Prime Minister Tony Abbott has said the government is considering what else Australia can do to usefully contribute to the international effort against Islamic State, and could add to the US military airstrikes that have halted the advance of the jihadist group into the Kurdish areas in Iraq.