A 12th person has appeared in court in connection with an alleged plot to bomb transatlantic airliners.
Umair Hussain, 24, from east London, is charged under the Terrorism Act with failing to disclose information which could help prevent an act of terrorism.
He was remanded until 1 September at City of Westminster Magistrates' Court.
Eleven other suspects have already been charged - eight of them with conspiracy to murder and preparing terrorism acts - and have been remanded in custody.
Mr Hussain was accused under section 38b(1)(a) and (2) of the Terrorism Act 2000 with failing to disclose information about his brother Nabeel Hussain, thought to be among eight people still being questioned by police.
The court heard how Umair Hussain was a graduate who had recently completed a Masters degree at a London university.
His solicitor, Tim Rustem, told judges that Mr Hussain was proud to be both British and Muslim.
Outside court, Mr Rustem said he was "in shock" at the decision to charge Mr Hussain.
"I'm very surprised at it, I expected to be walking out with my client this evening with him released without charge."
Mr Rustem said he believed his client had been charged for "tactical" reasons.
Another brother, 23-year-old Mehran Hussain, has already been charged with the same offence.
Mr Rustem and Zahir Ahmed, lawyer for Mehran Hussain, both indicated that they were considering mounting a legal challenge against the charges.
On Wednesday two people were released without charge after being held for 14 days as part of the same investigation.
Police have been given more time to quiz the eight other suspects over the suspected plot.