Nicaragua's parliament has authorized the establishment of a ground station in the Central American country for a Russian satellite network.
Nicaraguan officials say the base will permit the operation of GLONASS, a Russian satellite navigation system designed to be an equivalent of the United States' GPS.
Thy said it would be used for peaceful purposes such as mitigating natural disasters.
Opponents of President Daniel Ortega's ruling party say the measure, which originated as an urgent presidential decree sent to parliament this week, was pushed through without proper time for study.
Ortega had close ties to the Soviet Union as president in the 1980s, and has stepped up cooperation with Russia since returning to power in 2007.
Russian President Vladimir Putin visited Nicaragua last year.