Donald Trump has accepted the Republican Party's presidential nomination at the party convention in Cleveland, Ohio, setting up a showdown between the billionaire businessman and Democrat Hillary Clinton in November elections.

"We will be a country of generosity and warmth. But we will also be a country of law and order."

Mr Trump's singled out his opponent Hillary Clinton for allegedly breaking the law and getting away with it, which he says is her biggest achievement.

"Big business, elite media, major donors are lining up behind the campaign of my opponent, because they know she will keep our rigged system in place."

The delegates to the Republican National Convention had formally nominated Trump as the party's standard bearer earlier this week at a convention that has highlighted party divisions even as much of the party rank and file gushed about Trump's potential if he is elected president.

The Democrats will nominate Clinton at a party convention in Philadelphia beginning next week.

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