Russia’s parliament said on Thursday that any seizure of Russian assets by the European Union must be met by legal action against Belgium and securities house Euroclear, and Moscow could also take over the assets of investors from “unfriendly states”.

The Duma, parliament’s lower house, passed a resolution setting out the most explicit warning yet on how Russia would retaliate against an EU plan to use its frozen assets to fund a 140 billion euro ($161 billion) loan to Ukraine.

Lawmakers said the proposal “is effectively an illegal seizure of property, and therefore, if implemented, it can be regarded as outright theft.”

The resolution added: “Any attacks on Russian assets must be met with an appropriate legal response, beginning with claims for damages — with a demand for the seizure of assets as a security measure — against Euroclear and Belgium, where the bulk of the illegally frozen sovereign funds are held, in any jurisdiction.

“Assets of non-residents from unfriendly states may also be used as a source of compensation.”

After Russia went to war in Ukraine in 2022, Western governments froze some $300 billion of its assets, mostly in Europe. Of that, 185 billion euros are held in Euroclear, a Belgium-based securities depository.

The EU plan would be structured to avoid confiscating the assets outright – something that European authorities acknowledge could undermine investor confidence. It would involve issuing a loan to Ukraine using cash balances accrued from the frozen securities as they mature.

The scheme envisages that Kyiv would only repay the loan once it receives war reparations from Russia in a peace agreement – something Moscow has ruled out.

Ukraine has urged the EU to approve it quickly, saying it would use a significant portion of the funds to buy European weapons.

But the plan has been delayed because of concerns by Belgium, which says it needs strong assurances that the scheme is legal and that other EU countries will share the risks involved.

Belgian Prime Minister Bart De Wever called on all EU members at a summit last month to share the costs of any legal action pursued by Russia and to contribute financially if the money ever had to be paid back. He also said Russian frozen assets held by other countries should be part of the scheme.

The Kremlin has repeatedly said that attempting to take Russia’s assets will undermine confidence in the central banking system, in the euro as a currency, and in the perception of the safety of ownership and property rights in Europe.

Since the start of the war, Russia has seized tens of billions of dollars’ worth of assets held by foreigners there, including the Russian businesses of Western companies such as French food Danone and Danish brewer Carlsberg.

Moscow has also diverted an undisclosed volume of foreign-owned funds in Russia to so-called type-C accounts, access to which is blocked unless it grants a waiver.