US elections 2016: Trump wins five States, Clinton sweeps four

Republican front-runner Donald Trump has won presidential primaries in all five United States contests across the northeast states.

Hillary Clinton, who was dominant in four Democratic races, is now 90 percent of the way to the number needed to claim her nomination.

Trump called himself the Republican 'presumptive nominee' after victories in Connecticut, Delaware, Maryland, Pennsylvania and Rhode Island.

He swept all five primaries, winning landslides of more than 30 percentage points over his rivals Senator Ted Cruz of Texas and Gov. John Kasich of Ohio, reports New York Times.

The results bring him closer to the number of delegates he needs before the party's national convention in July.

Trump's and Clinton's wins propelled them ever closer to a general election showdown.

However, Sanders and Republicans Ted Cruz and John Kasich vowed to keep running, even as opportunities to topple the leaders are dwindling.

Trump still must negotiate a narrow path to keep from falling short of the delegates needed to claim the nomination before the Republican National Convention in July.

The Vermont senator won in Rhode Island and vowed to fight to the end of the primaries process.

Speaking at Philadelphia Convention Center after securing the four other states, Clinton said that her campaign was setting 'bold, progressive goals' to improve lives in the US.

The two Democrats have also been eyeing Indiana, with Clinton campaigning there on Tuesday.

Sanders has vowed to stay in the race until voting wraps up in June. He continues to raise millions of dollars and attract big crowds, including Tuesday night in West Virginia, where he urged his supporters to recognise they are 'powerful people if you choose to exercise that power'.

While Clinton's campaign expects Sanders to stay in the race, her advisers are eager for the Vermont senator to tone down his attacks on the former secretary of state.

Clinton has been reminding voters of the 2008 Democratic primary, when she endorsed Barack Obama after a tough campaign and urged her supporters to rally around her former rival.

The exit polls were conducted in Connecticut, Pennsylvania and Maryland.