The 27-year-old's two charges of possessing explosives stem from the recovery by United States forces of two caches of improvised explosive devices (IEDs) in Afghanistan in 2012.
Khalid Mohammed Omar Ali, 27, was arrested near Downing Street on April 27.
A man is led away by police in Westminster after an arrest was made on Whitehall in central London, Britain, April 27, 2017.
A man arrested near the British parliament last month was involved in bomb-making in Afghanistan in 2012, it was alleged Wednesday as he appeared in court on terrorism charges.
Flanked in the dock at Westminster Magistrates Court by two guards and wearing a grey top and pants, Ali said he did not recognise the charges and "not guilty" pleas were entered on his behalf.
Mr Omar Ali is believed to be a United Kingdom national who was born overseas and went to school in Tottenham.
Omar Ali has refused legal representation when it was offered to him.
He appeared in court wearing handcuffs and spoke to confirm his name, date of birth and address. Authorities said he had been under surveillance and had large knives in a backpack when he was detained.
When the charges were read out, Omar Ali said he did not recognise them.
Ali, who was not legally represented in court, was remanded in custody until 19 May.