The nonpartisan Congressional Budget Office Wednesday released a revised estimate of the cost of President Donald Trump's tax-cut bill passed by the U.S. House of Representatives, concluding it will add $2.4 trillion to the federal government's $36.2 trillion debt.

The new assessment comes a day after key Trump ally Elon Musk blasted the bill as a "disgusting abomination," giving fresh support to Republican deficit hawks who have been pushing back against the measure.

An earlier CBO estimate predicted the Republican bill, which passed on May 22 with no Democratic support, would add around $3.8 trillion to Washington's debt over the next decade.

The measure, now awaiting action in the Senate, aims to extend Trump's 2017 tax cut law while also achieving steep spending reductions, largely on a healthcare program for the poor.

The new CBO estimate takes into account late changes that were made to the bill as Republican leaders steered it to passage.