A man charged with attacking the White House Correspondents' Association dinner in Washington DC last month has pleaded not guilty.

Cole Tomas Allen, 31, was charged with federal gun crimes and attempting to assassinate US President Donald Trump.

The gun charges include using a firearm during a crime of violence and interstate transportation of a firearm with intent to commit a felony.

Allen appeared in court on Monday in an orange jumpsuit and was shackled at the wrists and feet, according to CBS News, the BBC's US partner.

Prosecutors allege that Allen attempted to storm past a security checkpoint and fired a shot at a US Secret Service agent at the event at a Washington Hilton hotel. The federal agent was hit in an exchange of gunfire but was saved by his bullet-proof vest.

Agents tackled Allen just short of a staircase that leads down to a ballroom where the annual White House Correspondents' dinner - attended by journalists, Trump and many top US officials - was getting under way.

The US president, Vice-President JD Vance, cabinet members, and a number of White House officials were rushed from the Washington Hilton hotel ballroom after the gunshots rang out.

Allen's appearance in court on Monday was his first time standing before US District Judge Trevor McFadden, who will preside over the remainder of the case.

His lawyers have requested Judge McFadden to disqualify all the US attorneys in the Washington office, including US Attorney for DC Jeanine Pirro from participating in the case, according to CBS News.

Allen's attorneys are also trying to remove Attorney General Todd Blanche from the case.

Eugene Ohm, a lawyer representing Allen, said they had presented themselves as victims of the attack in public statements and that it would be "wholly inappropriate" for the pair to be directing the prosecution of this case.

The justice department was directed to respond to the request by 22 June.

Authorities have said Allen left his home near Los Angeles in Torrance, California, on 21 April, and travelled by train to Chicago before heading to Washington.

In a memorandum filed by the US government last month, prosecutors say Allen took photos of himself in his hotel room at around 20:03 EST (1:03 BST), wearing dress clothes as well as a shoulder holster, pliers and wire cutters.

Photos included in the memorandum showed Allen posing in front of a mirror with several weapons strapped to his body, including a sheathed knife, and a bag with ammunition.

They alleged that during the following half hour, Allen checked several websites for live coverage of the White House Correspondents' dinner.

He then made his way downstairs and towards the ballroom, where the event was taking place.

Prosecutors said he sprinted through a metal detector, holding a shotgun with both hands in a raised position.