A Liberal government frontbencher has refused to say whether the federal budget will be in surplus this financial year as promised, instead saying the budget is “back on track”.

Labor’s finance spokeswoman Katy Gallagher reminded a Senate economics hearing on Thursday that Treasurer Josh Frydenberg boasted on budget night last April that the budget was “back in the black”.

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Senator Gallagher asked Assistant Minister for Financial Services Jane Hume – who was representing the government at the hearing – whether the federal budget “is back in black”.

Quoting Mr Frydenberg from parliamentary question time on Wednesday, Senator Hume replied: “The budget is back on track.”

Senator Gallagher asked whether “back on track” and “back in the black” are the same thing?

“I think you are getting into semantics,” Senator Hume said.

Senator Gallagher said it was an important semantic considering the government campaigned on the budget surplus trajectory at last year’s election.

“I think we can safely confirm that the budget is back on track,” Senator Hume reiterated.

Tweet from @SenKatyG

Last April, the Treasurer bragged of a $7.1 billion budget surplus for the 2019/20 financial year, which would be the first surplus in 12 years.

In December, at the mid-year financial update, he wound back expectations, forecasting a $5 billion surplus. Softening wage growth and growing warning signs for the economy were blamed.

Earlier on the Thursday, Treasury secretary Steven Kennedy told the committee in Canberra the bushfires and the emerging coronavirus epidemic will “undoubtedly have a negative impact on the fiscal position”.

The Morrison government is expected to unveil a multibillion-dollar stimulus package to counter the economic impact of the coronavirus outbreak next week.

Full details have not been released, but it is tipped to include tax incentives to help businesses with cash flow, alongside tax deductions for new investments.

Funding will be also aimed at infrastructure spending, which usually means major road and rail projects.

The latest budget forecasts will be released on May 12.

-with AAP