President Donald Trump holds up a proclamation during a White House ceremony to establish tariffs on imports of steel and aluminum at the White House in Washington, March 8, 2018.

In less than five months, the Trump administration has collected more than $1.4 billion in new revenue from steel and aluminum tariffs, according to a recent report prepared for members of Congress.

The Congressional Research Service estimated that, between March 23 and July 16, the U.S. reaped $1.1 billion and $344.2 million from levies on foreign steel and aluminum, respectively.

Those earnings are on the rise as trade negotiations with allies linger on and President Donald Trump moves to hike tariff rates on countries like Turkey. CRS says the new tariffs could reap the U.S. some $7.5 billion — $5.8 billion on steel and $1.7 billion on aluminum – based on last year's import levels. In 2017, the U.S. imported $29 billion worth of steel products covered the tariffs and $17.4 billion worth of aluminum.

Trump has suggested the tariffs – originally unveiled as a national security provision – could have the added benefit of reducing the federal deficit, which rose to $77 billion in July, wider than the July 2017 budget deficit of $43 billion. And the Treasury's borrowing to fund government operations is set to top $1 trillion this year for the first time ever.

"Because of Tariffs we will be able to start paying down large amounts of the $21 Trillion in debt that has been accumulated," Trump tweeted on Aug. 5. "At minimum, we will make much better Trade Deals for our country!"

@realDonaldTrump: ..Because of Tariffs we will be able to start paying down large amounts of the $21 Trillion in debt that has been accumulated, much by the Obama Administration, while at the same time reducing taxes for our people. At minimum, we will make much better Trade Deals for our country!

When asked about the revenue generated by tariffs on CNBC's "Squawk Box," Treasury Secretary Steven Mnuchin, demurred saying: "We're early in the stages, so I'm not going to give specific numbers … our long-term objective is not to collect tariffs. Our longer-term objective is to have free and fair and reciprocal trade."