Junead Ahmed Khan, 24, is accused of planning various terrorist acts, including a plot to run over a U.S. serviceman.
He and his 22-year-old uncle Shazib Ahmed Khan face charges of planning to travel to Syria to join ISIS.
The pair prepared to commit acts of terrorism between Aug. 1, 2010, and May 10, 2015, prosecutors said in London’s Westminster magistrates court Tuesday.
Junead Ahmed Khan alone faces a charge of plotting terrorism between May 10 and July 14, 2015.
Authorities did not release details about the alleged terror plot
They were arrested at separate residences in Luton, their hometown, last week and were remanded into custody until an Aug. 10 hearing.
The men, who prosecutors said looked into buying combat gear, spoke at the hearing only to confirm their names, the Guardian reported.
A third man who was also arrested on suspicion of terrorism last week was released without charge Monday.
Their arrests come less than a week after five U.S. military members were killed by a gunman who fired at a reserve base and recruiting center in Chattanooga, Tenn.