GENEVA (AP) — Swiss customs authorities said Friday that they are tracking about 3 tons of gold of Russian origin that entered Switzerland from Britain last month to watch for potential violations of economic sanctions against Russia following President Vladimir Putin’s war on Ukraine.

The gold is worth 194 million Swiss francs ($202 million), officials said.

The Federal Office for Customs and Border Security said it consistently monitors imports of gold from Russia, which it said are not prohibited under a raft of Swiss sanctions against Moscow imposed over Russia’s Feb. 24 invasion of Ukraine.

However, exports of gold to Russia are barred under Switzerland’s sanctions, the customs office said in a statement. Gold bars manufactured in Russia since March 7 can not be traded in Switzerland, but ones created before then can, the office said.

There are no commercial restrictions in Switzerland on other forms of gold, such as jewelry or coins, from Russia, the office said.

American news outlet Bloomberg first reported the imported Russian gold that Swiss authorities are reviewing.

The Swiss Association of Manufacturers and Traders in Precious Metals said Thursday it was aware of “concerns” linked to last month’s move and said none of its members — which includes the biggest smelters of gold in Switzerland — was behind it.

The association noted that while such imports are not illegal, it “would like to reiterate that dubious gold has no place in Switzerland and that it expects its members to act with the utmost caution and to refrain from buying in case of doubt.”

Switzerland has annually imported a total of about 270 billion Swiss francs (about $280 billion) worth of gold in recent years, according to customs office figures.

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