@osma
Issuing bonds with the Russian assets is not what is proposed, the collateral would still be EU assets.
Instead the idea is to service the bond payments using the interest on the Russian money, which makes putting in a collateral 'risk free', because the interest from the held assets would always cover the dues.
"The flow of income from Russia’s assets will continue. The EU could therefore launch and guarantee a vehicle whose debts are serviced using the income from Russia’s funds."