BORIS Johnson has come under pressure to halt exports of British arms and riot gear to the US after Donald Trump called for the authorities to "dominate" protesters and threatened to deploy the military.

Demonstrations have swept across America following the death of George Floyd while being restrained by police officers in Minneapolis.

President Trump has threatened to invoke the Insurrection Act, an 1807 law that allows a president to deploy the US military to suppress civil disorder, if state or city leaders refuse "to take the actions that are necessary to defend the life and property of their residents”.

Breaking his silence on the subject at Prime Minister’s Questions, Johnson said Floyd’s death was "inexcusable”.

The Tory leader commented: "I think what happened in the United States was appalling, it was inexcusable, we all saw it on our screens and I perfectly understand people's right to protest what took place.

"Though obviously I also believe that protest should take place in a lawful and reasonable way."

SNP Westminster leader Ian Blackford pressed the UK Government over the export of riot control equipment to the US, calling for an urgent review.

"The UK exports millions of pounds of riot control equipment to the US, including tear gas and rubber bullets," he said. “The Prime Minister must have seen how these weapons are used on American streets."

Blackford also asked the PM to state what “representations he’s made to his friend Donald Trump” about the unfolding crisis.

Johnson, side-stepping the question on his conversations with the US president, claimed the UK “is possibly the most scrupulous country” in the world when it comes to export checks.

Watch the full exchange below.

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It came as it emerged the UK Department for International Trade has issued a licence to an unnamed company to sell a range of crowd control items to US police and military buyers. They include CS hand grenades, anti-riot guns and projectiles, and tear gas capsules.

The Campaign Against the Arms Trade (CAAT) said almost £6 billion worth of arms sales to the US were approved since 2010, although it is not clear whether they were destined for the military or police.

CAAT spokesman Andrew Smith said: "The brutal and racist police violence we have seen over recent days has been absolutely appalling, and so has the reckless and totally irresponsible escalation from the President and his colleagues.

"These arms sales should never have been allowed and the Government must ensure that they do not happen again. This kind of equipment is always repressive, and it can be deadly."

A Government spokesman commented: "We take our export responsibilities seriously and assess export licence applications in accordance with strict licensing criteria."