BRUSSELS (AFP) ― European Union leaders urged Vladimir Putin to make a “radical change” in his stance on Ukraine Thursday as they boosted sanctions against Crimea despite fears of economic blowback from Russia’s spiraling financial crisis.

The leaders at a summit in Brussels also called for the urgent launch of a huge $380 billion investment plan aimed at kickstarting Europe’s moribund economy, although there were no pledges of hard cash.

Foreign policy chief Federica Mogherini said that while the collapse of the ruble was “not good news” for Russia, the EU or the world, sanctions would continue until Moscow stopped backing rebels in eastern Ukraine.

“President Putin and the Russian leadership should reflect seriously about the need to introduce a radical change in attitude towards the rest of the world, and switch to a cooperative mode,” she told reporters.

In the latest round of sanctions that have been coordinated with Washington, the EU agreed Thursday to ban all investment in Crimea and cruise ships from its ports as further punishment for Russia’s annexation of the region from Ukraine in March.

Western powers have repeatedly accused Russia of stoking the Ukraine crisis, which has killed at least 4,700 people and displaced close to 1 million, by supplying weapons and troops to the rebels ― which Moscow denies.

Leaders were trying to thrash out a “tough and responsible” policy on Russia over dinner, said new European Council president Donald Tusk, Poland’s Kremlin-wary former premier who is heading his first Brussels summit.

“We should send a strong signal on our readiness to further support Ukraine, also financially, as we have done politically today by making the existing sanctions on Crimea and Sebastopol more effective,” he said.

He joked that he felt like a “debutant with stage fright,” before ringing the tiny bell traditionally used to start the summit.

Tusk later said the leaders had agreed on the need to push forward European Commission president Jean-Claude Juncker’s flagship plan to invest in infrastructure and revive the bloc’s stalling economy.