A Russian facility that produces surface-to-air missiles (SAMs) has closed due to Western sanctions and import restrictions on key components, Ukrainian intelligence claimed on Sunday.

According to the Ukrainian Intelligence Directorate (GUR), the Ulyanovsk Mechanical Plant, which first opened in the 1960s, has shut down due to a lack of materials. The GUR claims that employees at the plant say "almost nothing Russian" is used when it comes to electronic components, most of which came from Germany.

"The production facilities of JSC Ulyanovsk Mechanical Plant have actually been stopped," the GUR said in a statement, according to a translation from the Ukrainian National News Agency, or Ukrinform.

"UMP is a manufacturer of radars and short-range and medium-range air defense systems for the Russian ground forces (Buk, Kub and Tunguska missile systems). The reason behind the critical state of production is the use of a large number of accessories and electronic components in the manufacture of military products."

The GUR reports that Russia attempted to create supply lines running through other countries, but found that the increased costs would force them over budget.

The report also states that plant employees are given a choice: to go on unpaid leave or sign a contract with the armed forces to fight in Ukraine. "The recommended position is an 'operator-gunner' of a Buk missile system. The proposed salary is 50,000 rubles a month," or about $600.

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