The Iranian foreign ministry has summoned Azerbaijan's ambassador over what it calls "baseless" accusations that Iranian agents helped plot a failed coup against the Baku government.
A Azerbaijani court last week convicted and sentenced 15 people on charges of conspiring with Iranian intelligence services to topple the secular government of President Ilham Aliyev.
An Iranian foreign ministry spokesman, Mohammad Ali Hosseini, Sunday called on the Baku government either to prove the allegations or to apologize for them. He also blamed Iran's "foreign enemies" for plotting to damage Iranian diplomatic ties with its northern neighbor.
In last week's trial, the accused leader of the plot, Sa'id Dadashbeyli, was sentenced to 14 years in prison.
Other members received lesser sentences. The verdicts came after a two-month trial in Baku held behind closed doors.
Group members were arrested in January and charged with high treason, plotting a coup, possession of illegal weapons and counterfeiting.
Azerbaijan's security agency said Saturday the alleged plotters had passed information on U.S., British and Israeli activities in the ex-Soviet republic to Iranian agents. It also said group members received training and cash from Tehran.
Some information for this report was provided by AFP, AP and Reuters.