KYIV - Russian missile and drone attacks on Wednesday heavily damaged two hydroelectric power plants in Ukraine, Ukraine's state-run hydropower generating company Ukrhydroenergo said Thursday.

"Two hydroelectric power plants are out of operation," Ukrhydroenergo said in a post on Telegram, not specifying locations.

Ukraine's overall hydroelectric power generation has suffered big losses in the recent attacks, it added.

The company said it would take "considerable efforts" and "significant financial resources" to repair and restore the destroyed facilities.

Ukrainian President Volodymyr Zelensky on Thursday met with visiting European Parliament President Roberta Metsola and discussed Ukraine's European integration and security issues

On Wednesday, Russia fired 55 missiles and 21 drones in an attack that targeted power generation and transmission facilities in six Ukrainian regions, according to Ukrainian authorities.

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Meanwhile, Ukrainian President Volodymyr Zelensky on Thursday met with visiting European Parliament President Roberta Metsola and discussed Ukraine's European integration and security issues.

At the talks, Zelensky said Ukraine has fulfilled all the necessary conditions for starting accession talks with the European Union next month, according to the presidential press service.

For her part, Metsola said she was optimistic that EU member states will adopt the negotiating framework for Ukraine in June.

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The European Parliament will help Ukraine in "all possible ways" to move along the European path, Metsola stressed.

Zelensky and Metsola also discussed the situation on the battlefield in Ukraine, the EU's defense support for Kyiv and the high-level conference on peace slated for mid-June in Switzerland.

Metsola arrived in Kyiv earlier in the day.