"State oil revenues have fallen considerably, and for the first time in a long time have become less than the national budget deficit," state secretary for finance Paal Bjornestad said in an email to AFP.
The government withdrew in January a net 6.7 billion kroner (€713 million, $780 million) from the fund -- much more than the 4.9 billion kroner forecast last year by the right-wing government for the whole of 2016.
The fund was as of early Friday stocked with a total 7.0 trillion kroner.
The sovereign fund, the world's biggest, is fuelled by Norway's huge oil and gas revenues and is intended to pay for future generations in the welfare-state after the country's wells run dry.
Its investment policy is run according to strict ethical rules, with a focus on sustainable economic, environmental and social development.
The government is only permitted to withdraw up to four percent from the fund to help balance its budget.
Norway, like other oil producing countries has been hit hard by the 70-percent fall in global crude prices since mid-2014 due to a supply glut.