Protesters have clashed with police outside a pro-Donald Trump rally in Washington DC, as tens of thousands of people prepare to take to the streets to oppose his presidency.

Demonstrators had gathered outside the National Press Club on Thursday night to oppose a group of Trump supporters who were staging a "DeploraBall", an event named after Hillary Clinton branded them a "basket of deplorables" during the election.

Footage posted on social media appeared to show police use pepper spray to disperse the protesters while smoke was also seen filling the street.

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Police announced later that a man had been charged with conspiracy to commit an assault.

The clashes came as tens of thousands of people prepare to stage protests in cities around the world on Friday when Mr Trump will be sworn in as US president.

Security officials have expressed concerns about possible clashes between supporters and opponents of Mr Trump in Washington, where up to 900,000 people are expected to watch him take the oath.

Coalition protest group DisruptJ20 has vowed to disrupt Mr Trump's inauguration and interfere with security checkpoints.

In contrast, Bikers For Trump will rally on Washington's Pennsylvania Avenue to celebrate Mr Trump's inauguration.

Outgoing homeland security secretary Jeh Johnson said 28,000 officials will be involved in the security operation in Washington, including more than 3,000 police officers and 5,000 members of the National Guard.

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He told MSNBC: "The concern is some of these groups are pro-Trump, some of them are con-Trump, and they may not play well together in the same space."

Film-maker Michael Moore will speak at a rally in Washington's McPherson Square on Friday afternoon, where some 20,000 people are expected to attend.

On Thursday, Moore was joined by Hollywood stars Robert De Niro, Julianne Moore and Alec Baldwin during a large protest outside Trump International Hotel in New York.

Anti-war group, the Answer Coalition, is planning demonstrations at the US Navy Memorial and Freedom Plaza near the White House.

Meanwhile, a group calling itself Occupy Inauguration plans to rally on the morning of the inauguration ceremony at Meridian Hill Park, about a mile and a half north of the White House.

The group said speakers at the rally will include 2016 Green Party presidential candidate Jill Stein.

In the UK, protests against Mr Trump will be staged in a number of cities including London, Edinburgh and Manchester.

The largest demonstration will take place in Washington on Saturday when some 200,000 people are expected to join a women's march.

Read more: Donald Trump has 'character problem' but presidency could change him, says Alex Salmond

Celebrities including Scarlett Johansson, Amy Schumer and Patricia Arquette have pledged they will attend the protest, while similar events are being planned in a number of US cities including Los Angeles and Park City, Utah.

Ugly Betty star America Ferrera, who is helping organise the Washington protest, said: "Since the election, so many fear that their voices will go unheard.

"As artists, women, and most importantly dedicated Americans, it is critical that we stand together in solidarity for the protection, dignity and rights of our communities."

Many of the women will be wearing pink knitted hats with cat ears - a reference to comments made by Mr Trump in a 2005 leaked video in which he bragged about grabbing women's genitals.