Donald Trump and Angela Merkel unable to conceal their differences in substance and style during first public appearance together

US President Donald Trump and German Chancellor Angela Merkel tried to sidestep their differences in a meeting at the White House on Friday but their first public appearance was punctuated by some awkward moments.

During a photo op in the Oval Office, the two did not shake hands before reporters. Trump pushed back against the notion in Europe that his “America First” agenda means he’s an isolationist, calling such a suggestion “another example of, as you say, fake news.” And he referred to the US as “a very powerful company” before quickly correcting that to “country”.

When a German reporter asked Trump if he regrets any of his commentary on Twitter, Trump said: “Very seldom.”

Merkel maintained her composure even when Trump repeated his contention that former president Barack Obama may have tapped his phones in Trump Tower. He sought to turn the explosive charge into a light joke when asked about concerns raised by the British government that the White House is now citing a debunked claim that UK spies snooped on Trump.

“At least we have something in common, perhaps,” Trump said casually, referring to 2013 reports the US was monitoring Merkel’s cellphone conversations. As for the most recent report, Trump said he shouldn’t be blamed for quoting a Fox News analyst who had accused British intelligence of helping Obama spy on him.

When the subject turned to economic issues, Merkel attempted to project a conciliatory approach. She said the “success of Germans has always been one where the German success is one side of the coin and the other side of the coin has been European unity and European integration. That’s something of which I’m deeply convinced.”

Those comments appeared aimed at making a case to Trump on the benefits of the European Union. Trump backed Britain’s departure from the EU and has expressed scepticism of multilateral trade agreements.

The two leaders tried to express their common bonds but showed minimal rapport in their first encounter, a departure from Merkel’s warm relations with Obama during his eight years as president. At the start of the news conference, Merkel sought to break the ice, saying that it was “much better to talk to one another than about one another”.

Merkel said delicately that while she represents German interests, Trump “stands up for, as is right, American interests. That is our task respectively”. She said they were “trying to address also those areas where we disagree but tried to bring people together”.

“We need to be fair with each other,” Merkel said, saying both countries were expecting “that something good comes out of it for their own people”.

Trump later said on Twitter Germany owes “vast sums of money” to Nato and the US “must be paid more” for providing defence.

In a tweet from his Florida resort, where he is spending the weekend, Trump wrote that he had a “GREAT” meeting with German Chancellor Angela Merkel, despite reports to the contrary.

But he reiterated his stance that Germany needs to meet its end of the bargain if it is to continue benefiting from the military alliance.

Trump wrote: “Despite what you have heard from the FAKE NEWS, I had a GREAT meeting with German Chancellor Angela Merkel.”

He added, “Nevertheless, Germany owes ... vast sums of money to NATO & the United States must be paid more for the powerful, and very expensive, defense it provides to Germany!”

The meetings at the White House included discussions on strengthening Nato, fighting Islamic State, the conflict in Afghanistan and resolving Ukraine’s conflict, all matters that require close cooperation between the US and Germany.

The talks, postponed from Tuesday because of a snowstorm, aimed to represent a restart of a relationship complicated by Trump’s rhetoric on the campaign trail. As a candidate, Trump frequently accused the chancellor of “ruining” Germany for allowing an influx of refugees and other migrants from Syria and accused his campaign rival, Hillary Clinton, of wanting to be “America’s Angela Merkel”.

During the news conference, Trump predicted that a new health care law would be passed by a substantial margin and “pretty quickly,” expressing optimism for his top legislative priority.

The new president reaffirmed the US’s “strong support” for Nato but reiterated his stance that Nato allies need to “pay their fair share” for the cost of defence. Trump said many countries owe “vast sums of money” but he declined to identify Germany as one of the nations.

Prior to his inauguration, Trump declared Nato “obsolete” but has since modified his stance, telling European leaders the alliance remains of strategic importance. Only the US and four other members currently reach the benchmark of spending 2 per cent of GDP on defence. Germany currently spends 1.23 per cent of its GDP on defence, but it is being increased.

Both leaders pointed to their work on the conflict in Afghanistan and efforts to combat terrorism.

When the topic moved to trade, Trump said the US would do “fantastically well” in its trade relations with Germany. The president has been deeply critical of foreign trade and national security agreements but suggested he was only trying to revise trade deals to better serve US interests, rather than pull back from the world entirely.

Trump said trade agreements have led to greater trade deficits. The US trade deficit with Germany was US$64.9 billion last year, the lowest since 2009, according to the Commerce Department.

“The negotiators for Germany have done a far better job than the negotiators for the United States, but hopefully we can even it out. We don’t want victory, we want fairness,” Trump said.

Merkel emphasised the need for trade deals that fairly benefit both countries.

“That is the spirit I think in which we ought to be guided in negotiating any agreement between the United States of America and the EU,” she said.