US President Donald Trump's approval rating has dropped once again, while House Speaker Paul Ryan is now the most unpopular politician in the US, according to a new survey from Public Policy Polling.

Just 40% of the people polled approve of the president, while 53% of people disapprove of him – the lowest Trump's approval rating has been in PPP polls.

In particular, Trump's failed push to repeal and replace Obamacare did not go down well with voters, with polls revealing the Affordable Care Act is now more popular than it has been in its recent history.

"The main thing that this month's healthcare fight in Washington did was make Obamacare more popular than it's ever been before," said Dean Debnam, President of Public Policy Polling, in a statement.

"There's little appetite from voters to repeal it at this point."

The failed healthcare push has also had a knock-on impact on Ryan, whose own approval rating has dropped in the wake of the House cancelling the vote on healthcare.

In fact, the PPR poll shows Ryan is currently the least popular politician in the country, with an approval rating of just 21% and a disapproval rating of 61% – a precipitous drop from his previous approval rating of 33% at the very beginning of Trump's term.

Voters also hold Ryan more culpable than Trump for the failed healthcare push. According to the poll, 54% of Republican voters blame Ryan compared to just 13% who blame Trump.