Strong economic figures have helped US President Donald Trump to his highest approval ratings ever, despite impeachment, a new poll found Monday.

Although the Quinnipiac University survey said Trump has a high of 43 percent for his job approval, that's still far below nearly all previous presidents in modern times at the same point in their administration.

According to the poll, carried out December 11-15, 52 percent of Americans still disapprove of Trump's job performance. Trump has been mired in those unusually low ratings for nearly his entire presidency.

But the latest figures show a progression indicating support growing for Trump despite the impeachment process threatening his presidency. The House of Representatives could vote to impeach for abuse of office and obstruction of Congress as early as this Wednesday.

A Quinnipiac poll earlier in December had 41 percent approval and 55 percent disapproval, while an October poll, done before impeachment hearings began, put those figures at 38 and 58 percent.

Nearly three quarters, 73 percent, saw the economy as good or excellent, the poll found.

The poll found little changed figures on impeachment, with 45 backing Trump's impeachment and removal from office and 51 percent opposing. Support for impeachment and removal back in October was at 45-48 percent.

Not surprisingly, the poll looks radically different when the answers are divided by party. Ninety five percent of Republicans oppose removing Trump from office, while 86 percent of Democrats are in favour.