Gen. Saldiray Berk, commander of Turkey's 3rd Army based in Erzincan province, was named on Monday as the top suspect in an anti-Islamist campaign aimed at discrediting the AK Party of Prime Minister Tayyip Erdogan.
Berk is the highest-ranking serving officer to have been charged among scores of retired and active officers detained since last week.
Tens of thousands of soldiers were to take part in the operation on Wednesday near the border with Armenia at Sarikamis, where more than 60,000 Turkish soldiers died in a battle with Russian forces during World War I.
The two-day exercises are held every two years. The head of the armed forces, General Ilker Basbug, is scheduled to attend on Thursday.
Erdogan attended the 2006 operation but was not scheduled to attend this time. The 2008 exercises were canceled due to operations in northern Iraq against Kurdish guerrillas.
Last week's detentions of dozens of officers were related to an alleged plan for a military coup in 2003, but the case against Berk is more recent.
Such action against the powerful, staunchly secularist military would have been unthinkable just a few years ago, but reforms aimed at supporting Turkey's bid for EU membership have reduced the influence of the armed forces.
The charges brought against Berk and 15 others, including a state prosecutor, are linked with a suspected ultra-nationalist network known as "Ergenekon" that was said to be plotting to sow chaos in order to justify a military takeover.
More than 200 people, including retired generals, lawyers and journalists, have been charged in connection with Ergenekon.
The plan in Erzincan is alleged to have involved fomenting nationalist opposition to the government and planting weapons in houses used by followers of influential preacher Fethullah Gulen to create a scare about Islamic militancy.
Gulen has lived in self-imposed exile in the United States since 1999, but critics say his followers have infiltrated the police and courts, and also control newspapers critical of the army.
