The United States is more divided than it has been for decades, with ultra-conservative Republicans and left-leaning forces within the Democrats widening the gap between the two parties.

It is a nation so polarised that eight out of 10 Americans say that they disagree with the other party not only on policy but basic facts. The most divisive issues are the two parties' differing views on President Donald Trump, gun control, abortion and immigration.

The country is fractured down party lines. There has been a hollowing out of the middle ground of US politics and supporters of both sides are becoming increasingly partisan.