Federal Treasurer Joe Hockey has admitted he will be forced to make more “realistic” budget forecasts in response to slowing world growth and falling commodity prices.

In an interview with The Australian, Mr Hockey admitted there had been a “hit to the budget”, but would not go into detail about what impact it would have on government deficit.

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The report alleges export prices could fall further than originally estimated in the May budget, which could translate to a $5.4 billion increase in deficit by next year.

The information comes as the International Monetary Fund marked down global growth forecasts, urging political leaders in a new report to “try harder” to create jobs and boost demand.

“We’ve got to be realistic about the state of the economy and the state of the budget,” Mr Hockey said.

He denied that the half-year budget update would mean a new set of measures and savings to deal with gridlock in the senate.