LONDON — US National Security Advisor John Bolton was Monday to sound out British Prime Minister Boris Johnson on global disputes that include an escalating Gulf standoff with Iran.

The hawkish White House aide is the most senior US official to meet Johnson since he succeeded Theresa May as UK government leader last month.

A spokesman for Johnson said the two would talk about "a range of security issues, including Iran".

The meeting comes with US President Donald Trump's administration pursuing a "maximum pressure" campaign designed to force the Islamic republic to limit nuclear and military activities.

Washington also wants its close European ally to drop — or at the very least severely restrict — plans to use 5G technology made by China's Huawei when it rolls out the next-generation data network.

US media reports said Washington was not expecting a decision from London on either issue during Bolton's two-day visit.

The Downing Street spokesman said London's position on both Iran and Huawei "remains the same".

Bolton's trip comes with Britain in political crisis and the pound straddling multi-year lows as deadline approaches for the UK to leave the EU after more than 40 years.

Johnson has vowed to meet the twice-delayed Brexit date — now Oct. 31 — even if it means leaving without a proper plan to regulate trade and other ties.

Senior UK economic officials and big industries warn that this "no-deal Brexit" option could create border chaos and set off global financial tremors in the short term.

The EU is refusing to re-open negotiations on the deal the bloc's 27 leaders signed last year with May. Johnson and his supporters call the existing agreement unfair.

But a clean break with the EU would allow the UK to immediately launch negotiations on a free trade agreement with the United States.

The US president openly rooted for Johnson during his campaign for May's job following her resignation over the Brexit impasse.

He branded Johnson as Britain's Trump and said the sides were on the verge of making a breakthrough in ties.

Britain and its European allies have irritated Trump's team by trying to save a landmark nuclear agreement with Iran which Washington pulled out of last year.

Britain last week decided to join forces with the US to protect merchant vessels in the Gulf.

It marked a departure in policy for Johnson following May's attempts to form a European-led group.

Britain's decision on Huawei — a private firm that Washington says is obliged to spy for the Chinese government — has been repeatedly delayed due to mixed signals from Trump about his own administration's next steps.

Johnson's spokesman said the UK government was "still assessing the impact" of Trump's decision in May to effectively ban Huawei from trading with US firms. — AFP