The U.S. federal budget deficit exceeded one trillion U.S. dollars in the first 11 months of the fiscal year 2019, up by 18.8 percent from the same period the previous year, the Treasury Department said Thursday.

The 11-month deficit, from October last year to August, registered 1.067 trillion dollars, the highest level since 2012, according to data from the Monthly Treasury Statement. The budget deficit for the last fiscal year totaled 779.0 billion U.S. dollars.

The top three outlays for the 11 months were 956 billion U.S. dollars on social security, 632 billion dollars on national defense, and 625 billion dollars on Medicare.

In its most recent baseline projections, the Congressional Budget Office (CBO) estimated that the 2019 budget deficit would be 960 billion dollars. "The deficit for the year is expected to be smaller than the shortfall in first 11 months because tax payments due in September are likely to yield a surplus in that month," the CBO said in its latest monthly budget review.

In July, the White House projected a one trillion U.S. dollar budget deficit for the fiscal year 2019, as stated by the Office of Management and Budget in its Mid-Session Review.

Earlier in August, U.S. President Donald Trump signed the "Bipartisan Budget Act of 2019," which boosts discretionary spending limits and suspends the public debt limit for the next two years.

The budget deal will lift the budget cap for discretionary spending to 1.37 trillion U.S. dollars in 2020 and 1.375 trillion U.S. dollars in 2021, expanding defense outlays, demanded by Republicans, and boosting domestic spending, including health care for veterans, sought by Democrats.