Clinton and Trump win crucial New York presidential primary

Manhattan billionaire Donald Trump and former secretary of state Hillary Clinton won the New York primary on Tuesday, galvanising their bids to win the Republican and Democratic nominations for the White House.

US networks called the race for the Republican frontrunner seconds after the polls closed in the country's fourth most populous state, signaling a crushing victory over his rivals.

"I have to say to the people that know me the best - the people of New York - when they give us this kind of a vote it's just incredible," the 69-year-old businessman told a victory party at Trump Tower in Manhattan. 

He told supporters his campaign was going to "get a lot more delegates than anyone projected even in their wildest imagination".

Clinton was declared the winner over Vermont Senator Bernie Sanders around 40 minutes after the polls closed. With 95 percent of the 1.4 million votes tallied, Clinton led 57.7 percent to 42.3 percent and was ahead in New York City.

Some Sanders supporters complained about the restrictive voter registration system in New York, which removed thousands of voters from the rolls and prevented independents from voting in the Democratic primary. 

Clinton had banked on victory in her adopted home state to stall the momentum generated by her self-styled democratic socialist rival and get a needed shot in the arm after losing seven out of the eight previous nominating contests.

It was New York's most decisive primary in decades and Trump's victory in the state, which has 95 Republican delegates in play, will bolster his quest to sew up the nomination before party grandees can swing behind another candidate at the convention in July.

While New York City is largely Democrat, Republicans in rural areas and fallen manufacturing cities upstate warmed to Trump's populist message, despite his insults towards women, Mexicans and Muslims.

At a recent debate in New York, Clinton and Sanders exchanged barbs over the Israeli-Palestinian conflict as well as Syria and Libya.

Clinton defended her peace-making efforts in the decades-old conflict and said that Israel is engaged in a brutal battle with Hamas – a Gaza-based militant group that receives weapons from Iran, she said.

“I don't know how you run a country when you are under constant threat, terrorist tactics, rockets coming at you. You have a right to defend yourself,” Clinton said.

Sanders blasted Clinton for voting for the 2003 US-led invasion of Iraq and spearheading its 2011 bombing campaign in Libya that helped topple its leader Colonel Muammar Gaddafi.

“We didn’t think thoroughly about what happens the day after you get rid of these dictators,” said Sanders.

“Regime change often has unintended consequences in Iraq and in Libya right now, where ISIS has a very dangerous foothold,” he added, using an acronym for the Islamic State (IS) group.

Sanders also criticised Clinton’s support for a failed bid to arm moderate Syrian units in their fight against President Bashar al-Assad’s forces and in her support for a no-fly zone over parts of the war-ravaged country.

“It will cost an enormous sum of money [and] … it runs the risk of getting us sucked into perpetual warfare in that region,” Sanders said.

Clinton defended herself, suggesting that a faster military response in Syria could have halted a spiralling conflict that has claimed some 470,000 lives, according to one estimate, and forced millions from their homes.

“Nobody stood up to Assad and removed him, and we have had a far greater disaster in Syria than we are currently dealing with right now in Libya,” she told the audience.

“And, yes, I do still support a no-fly zone because I think we need to put in safe havens for those poor Syrians who are fleeing both Assad and ISIS and have some place that they can be safe.”

Clinton currently leads with 1,791 compared to 1,115 for Sanders, according to a CNN tally - putting her on course to clinch the 2,383 delegates needed to secure the party's presidential nomination.

It was not immediately clear how many of the 247 Democratic delegates and 44 superdelegates up for grabs in New York will be accorded to Clinton.