US President Donald Trump said the administration was studying a tax cut for middle-income earners that could be rolled out sometime around the beginning of November, just before pivotal congressional elections.

Trump mentioned the proposed tax cut in the same week the US government ended the 2018 fiscal year with a 779 billion US dollar deficit, the Treasury Department said on Monday, as previous Republican-led tax cuts squeezed revenues. The deficit figure was the highest in six years.

"We're looking at putting in a very major tax cut for middle-income people," Trump told reporters before boarding Air Force One following a rally in Elko, Nevada.

When asked about timing for the unveiling of the tax cuts, Trump said "sometime around the first of November, maybe a little before."

Americans will vote November 6 in elections in which Trump's fellow Republicans will try to hold on to their majorities in the Senate and House of Representatives.

The median household income in the United States was about 55,000 US dollars in 2016, according to the US Census Bureau.

In December, Trump signed into law the largest tax overhaul since the 1980s, which slashed the corporate rate from 35 percent to 21 percent and temporarily reduced the tax burden for most individuals as well.

The administration is beginning to pull together plans for the president's fiscal 2020 budget proposal, which Trump will present to Congress early next year.

On Wednesday Trump told his Cabinet to come up with proposals to cut spending by their agencies by five percent but he suggested the military would be largely spared.