Thanks to Twitter he will be just 280 characters away.

Ms Bishop and Ms Payne will meet with US Secretary of State Mike Pompeo and Defense Secretary James Mattis on Monday and Tuesday at Stanford University, near San Francisco, for the annual AUSMIN talks.

A long list of issues are on the agenda, including the latest on the North Korea nuclear talks, infrastructure, trade, tariffs, the continued fight against Islamic State and China's island building in the South China Sea, meddling in the South Pacific and theft of intellectual property.

Mr Pompeo and General Mattis have been dubbed by some US political commentators as two of the "adults" in the Trump administration.

Mr Trump, however, has shown in recent weeks whether it was in Singapore with North Korean leader Kim Jong-un, in Brussels with NATO partners, in Helsinki with Russian President Vladimir Putin or on Thursday at the White House, that his most important advisers are often left in the dark about his major moves.

"Say that again?" Mr Trump's Director of National Intelligence, Dan Coats, said with surprise when told mid-interview on stage at the Aspen Security Forum on Thursday the president had invited Mr Putin to visit Washington DC later this year.

White House Press Secretary Sarah Sanders announced the planned visit on Twitter and Mr Coats was clueless about it.

Mr Coats also said he was still not sure what Mr Trump and Mr Putin spoke about in their two-hour plus closed door meeting in Helsinki on Monday.

"You're right, I don't know what happened in that meeting," Mr Coats said.

Australian Prime Minister Malcolm Turnbull, Ms Bishop and Ms Payne have ridden a roller-coaster of highs and lows with Mr Trump since his election victory in November 2016.

Mr Turnbull had that rough phone call over the asylum seeker deal with Mr Trump a week after the president moved into the White House.

The two leaders managed to mend their relationship through carefully-managed events that promoted the long, trusted relationship the US and Australia shared.

There was the May 2017 black-tie dinner on the USS Intrepid aircraft carrier on New York's Hudson River to commemorate the 75th anniversary of the Battle of the Coral Sea.

There was also the creation of the "100 Years of Mateship" slogan.

In February, Mr Turnbull and Mr Trump had a cosy meeting at the White House.

Proof Australia's charm offensive had worked was Mr Trump's decision to spare Australia from the aluminium and steel tariffs he slapped on almost every other nation on Earth.

The Australian government, through trial and error, had worked out how to deal with Mr Trump.

"The international scene, for as long as I have been involved in politics, has been filled with characters who do not fit into square boxes and on this occasion it happens to be the president of the United States," Ms Payne, in Scotland ahead of flying to California, said.

A senior State Department official told reporters on Thursday the site for this year's AUSMIN has special meaning because the ANZUS treaty was signed in San Francisco in 1951.

The talks will broach difficult topics, but are still expected to be a largely jovial affair between the closest of allies.

That, of course, could change with just one crisis-causing tweet from @RealDonaldTrump.

Australian Associated Press