Finance Minister Mathias Cormann has rejected former treasurer Peter Costello's claim that the coalition lacks an economic narrative, saying it talks about the economy "day in, day out".

Mr Costello told an event last week the government was operating in a "parallel universe" by promising tax reforms in 10 years time, a sentiment with which Senator Cormann disagrees.

He says politicians are often criticised for taking a short-term view, but the government is looking further.

"We seek to make decisions that put Australia on the stronger trajectory for the future," he told ABC TV on Sunday.

"We seek to make decisions that have a beneficial effect over the medium and long term."

The minister said the coalition discussed the economy "all the time".

"I talk about the economy, the prime minister, the treasurer, all of my colleagues. We talk about the economy, day in, day out," he said.

"Our economic mission is to deliver more jobs so that more Australians have the best possible opportunity to get ahead, and improve their living standards for themselves and their families."

Senator Cormann has also dismissed Labor's claim that the coalition has ditched one its fundamental budget rules to deliver tax cuts for small and medium sized businesses, five years earlier than planned.

The coalition revealed plans this week to fast-tracked tax relief for businesses with turnovers of less than $50 million, who will have their tax rate dropped to 26 per cent rate in 2020/21, then to 25 per cent the following year.

Such businesses already had their rate reduced from 30 per cent to 27.5 per cent last year.

Labor revealed on Friday it would also back the plan. It would pay for its $3.2 billion cost by delaying for a year another of its policies, reducing the cost of new assets for businesses.

Deputy Labor leader Tanya Plibersek said the coalition wants to pay for the tax relief by taking advantage of recent economic growth - breaking its promise to use any unexpected growth gains to pay down debt.

"They've just chucked that out the window," she told Sky News on Sunday.

Senator Cormann said Labor is confused about the difference between a tax cut and new government spending.

"It should be clear to everybody else that reducing taxes is not increasing government expenditure," he said.

The government will introduce legislation for the fast-tracked cuts to parliament next week.