A US court on Thursday jailed a 53-year-old Russian to 18 months with three years supervised release for conspiracy to smuggle high-tech night vision technology out of the country.

The sentencing comes with US-Russian relations at their worst since the end of the Cold War, reeling from the crisis in Ukraine and at loggerheads over the civil war in Syria.

Dmitry Ustinov was arrested in Lithuania at the request of the US government in April 2013 and extradited to Delaware to stand trial for arms smuggling, despite protests from Russia.

He pleaded guilty to conspiracy to export high-tech military technology and has already served nearly 18 months in custody.

The US Justice Department said Ustinov, from Moscow, would be deported upon his release from an American federal prison.

According to court documents, he caused or attempted to cause the export of 17 night vision devices and thermal imaging scopes, which US law designates as weapons and prohibited for export.

The devices he sought to ship overseas are primarily mounted on weapons or helmets, or even vehicles, planes and drones.

Ustinov tried to conceal his plot by wiring money from front companies located in offshore accounts in Cyprus, falsely labeling packages to avoid detection by customs agents and discussed concealing them inside chopped-up car parts.

Prosecutors said Ustinov never applied or received a US government export license.

"It is important that we take all necessary steps to prevent our military technology from being exported and possibly used against our service members and our allies overseas," Delaware District Attorney Charles Oberly said.

Lithuania, which broke free from the Soviet Union in 1990, is a NATO and EU member, and one of the staunchest allies of the United States in Europe.