The U.S. federal government posted its biggest budget deficit in six years as spending increased in fiscal year 2018, the Treasury Department reported.

The budget deficit widened to $779.00 billion in the fiscal year that ended in September from $665.83 billion in the previous fiscal year.

Government outlays climbed to $4.108 trillion in fiscal year 2018 from $3.981 trillion a year earlier, with defense spending increasing to $600.71 billion from $568.91 billion.

Federal revenues rose to $3.329 trillion from $3.315 trillion in fiscal year 2017, as corporate income tax receipts fell to $204.73 billion from $297.05 billion. Revenues from individual income taxes rose to $1.684 trillion from $1.587 trillion.

The shortfall was the biggest since fiscal year 2012, when the government posted a shortfall of $1.089 trillion.

In September, the government ran a monthly budget surplus of $119.12 billion, topping Econoday's forecast of a $77.5 billion surplus and following a $214.15 billion deficit in August.