A Canadian woman has been charged in US federal court for allegedly posting a letter with deadly ricin poison to President Donald Trump.

Pascale Ferrier, of Quebec, was arrested at a border crossing in Buffalo, New York, on Sunday. Officials say she was carrying a gun. She has pleaded not guilty to making threats against the president.

The letter she allegedly sent last week was discovered before it reached the White House. In it, she called on Mr Trump to drop out of the US presidential race. The envelop contained ricin, a poison found naturally in castor beans. “I found a new name for you: ‘The Ugly Tyrant Clown’,” she wrote in the letter to Mr Trump, according to FBI charging documents filed ahead of her first court appearance in New York on Tuesday. “I hope you like it. You ruin USA and lead them to disaster. I have US cousins, then I don’t want the next 4 years with you as president. Give up and remove your application for this election.”

The letter, which the FBI says had her fingerprints on it, referred to the poisoned note as “a special gift”, adding: “If it doesn’t work, I’ll find better recipe for another poison, or I might use my gun when I’ll be able to come. ” The suspect may have also sent ricin to five addresses in Texas, including a jail and a sheriff’s office, according to the court documents.

Ms Ferrier appeared in court on Tuesday afternoon in Buffalo, New York, with the aid of a French-speaking translator, according to local media. She asked for a court appointed defence lawyer during the hearing. That lawyer also requested an identity and probable cause hearing, to have the court determine that she is the individual named in the complaint.

The judge scheduled these next hearings for 28 September. She will be in the custody of the US Marshals until that time, as prosecutors argued she poses a flight risk.