Europe desperately wondering what to do about Ukraine

After Vladimir Putin's dismissal of the latest Europe/US/Ukraine peace proposal, European leaders are left floundering. They know that Trump has probably now had more than enough and would like to get shot of Ukraine which will leave the Europeans to fill the gap to help Zelensky continue to fight the Russians. Nothing they can come up will persuade Putin to compromise at any time in the near or far future, and, anyway, the Russian president has totally taken against Europe. If they want war with Russia, they can have it, he said the other day. Well, of course Europe doesn't want war with Russia but nor does Europe want Russia to win the war in Ukraine. So, there is massive bafflement and concern. What on earth can they do about Putin? The answer is pretty much nothing, especially if Trump backs off. The US is still sanctioning Russia's two biggest oil producers but Putin seems not to be overly worried. The only thing Europe can do is grab all of Russia's frozen assets in western banks, mostly in Belgium for some reason, and use it to send more weapons to Ukraine. But Putin might regard this as both illegal and an attack on Russia. Then what? As I said, Europe is floundering.