Xenophon to kill off big business tax cut

Nick Xenophon's team looks set to sink the boot into the Turnbull government's 10-year plan to cut the tax rate for big business to 25 per cent.

The government must woo nine of 11 votes on the Senate crossbench - the Greens have ruled out supporting the proposal and Labor will only back tax cuts for companies with revenue less than $2 million.

Senator Xenophon's team has three votes in the Senate and he has told the Financial Review his decision not to back the plan is final.