Donald Trump's expressed his delight at the US Senate's approval of the biggest reform to America's tax system in more than three decades.

The president's tweeted the country's 'one step closer to delivering massive tax cuts for working families'.

But Democrats say the Republican bill will mostly benefit big businesses.

We are one step closer to delivering MASSIVE tax cuts for working families across America. Special thanks to @SenateMajLdr Mitch McConnell and Chairman @SenOrrinHatch for shepherding our bill through the Senate. Look forward to signing a final bill before Christmas! pic.twitter.com/gmWTny3SfS

— Donald J. Trump (@realDonaldTrump) December 2, 2017