Australian Prime Minister Malcolm Turnbull enjoyed a private discussion with US president Donald Trump on the first day of the G20 Summit, where North Korea’s provocative nuclear tests, terrorism and climate cast a shadow over talks.

On Friday evening, Mr Turnbull and his wife, Lucy, joined Donald and Melania Trump for a ride in their armoured presidential vehicle, where the two leaders had a “private discussion”.

The eight tonne limousine, nicknamed “The Beast”, follows the US President around the world and features five-inch thick bulletproof glass, Kevlar tyres, rocket-propelled grenades and tear gas cannons.

“I felt very safe,” Mr Turnbull laughed afterwards. “It was very kind of him.

“We went from the reception to the concert theatre, it was an opportunity to have a good private discussion. We talked about a number of things, including some old mutual friends.”

Mr Turnbull left the summit in Hamburg to head straight for Paris to hold talks with French President Emmanuel Macron on Saturday.

Before leaving, Mr Turnbull rejected suggestions of implementing a missile defence system in Australia in response to North Korea’s nuclear weapons development.

“That’s not really suitable for our situation, but I can assure you we are constantly examining how we can ensure that Australians are safe,” he told reporters.

Mr Turnbull also placed the onus on China to take the “strongest action” against the rogue nation.

“The nation with overwhelmingly the greatest leverage over North Korea is China. And so we look to China to bring North Korea to its senses,” he said.

Mr Turnbull said he had spoken to China’s President Xi Jinping who asserted, “the situation is not as straightforward as others assert and that their influence is not as great as others assert it is”.

Riots and Beethoven

As protestors fighting against capitalism and globalisation torched cars, looted stores and blasted Jimi Hendrix songs, the world’s leaders took a break from discussions on Friday evening to listen to Beethoven’s Ninth Symphony.

The world leaders sent staff away to work through Friday night to find agreements on trade and climate change while they attended a concert at the Elbphilarmonie concert hall.

“The sherpas have a lot of work ahead of them tonight,” German Chancellor Angela Merkel said, referring to the trade dossier. “I hope they can bring us a good result tonight.”

Speaking about the protests, Ms Merkel said she had hoped to see more peaceful reactions to the summit.

“I have every understanding for peaceful demonstrations but violent demonstrations put human lives in danger,” she said.

Melania trapped

Amid the violent clashes, US First Lady Melania Trump and other spouses of world leaders were trapped in their hotels after police declined to allow them to tour Hamburg’s sights early on Friday.

“The Hamburg police could not give us clearance to leave [the residence],” said Mrs Trump’s spokeswoman Stephanie Grisham.

Putin meets Trump

On the sidelines of the G20 summit, US President Donald Trump and Russian President Vladimir Putin held their much-anticipated first meeting.

The White House said 35 minutes had been allotted for their private discussion, but the chat lasted more than two hours, with Mrs Trump being sent in, unsuccessfull, to wrap the conversation up.

US Secretary of State Rex Tillerson said Mr Trump raised “robust and lengthy” concerns about Moscow’s meddling in 2016 presidential election.

Russian Foreign Minister Sergey Lavrov, who attended the meeting alongside Tillerson, said Mr Trump accepted Mr Putin’s assurance Russia did not meddle in the US election.

Merkel’s major eye roll

The G20 also produced some memorable snafus and media-worthy gaffes from the world’s politicians.

Most notably, host Ms Merkel was caught rolling her eyes during an animated discussion with Russian president Mr Putin, prompting plenty of online discussion.