WASHINGTON (Reuters) - U.S. President Joe Biden said on Monday that deadly Russian missile strikes in Ukraine, including on the main children's hospital in Kyiv, were "a horrific reminder of Russia's brutality."

WHY IT'S IMPORTANT

Russia blasted the hospital in Kyiv with a missile in broad daylight on Monday and rained down missiles on other cities across Ukraine, killing at least 36 civilians in the deadliest wave of air strikes for months.

Washington has been the biggest supporter of Ukraine amid Russia's invasion that began in February 2022. The U.S. has provided Ukraine with more than $50 billion in military aid since 2022. As world leaders prepare to head to a NATO summit that starts on Tuesday in Washington, Ukraine has called on Kyiv's partners to give a firm response to Monday's attack.

KEY QUOTES

"Russia's missile strikes that today killed dozens of Ukrainian civilians and caused damage and casualties at Kyiv's largest children's hospital are a horrific reminder of Russia's brutality," Biden said in a statement released by the White House.

Biden added in his statement that Washington and its NATO allies will be announcing this week new measures to strengthen Ukraine's air defenses.

"It is critical that the world continues to stand with Ukraine at this important moment and that we not ignore Russian aggression," Biden said.

CONTEXT

President Volodymyr Zelenskiy said Ukraine would retaliate and called on Kyiv's Western allies to give a firm response to the attack.

Moscow has repeatedly denied targeting civilians and civilian infrastructure, although its attacks have killed thousands of civilians since it launched its invasion.

The Russian Defence Ministry said its forces had carried out strikes on defence industry targets and aviation bases in Ukraine.

(Reporting by Kanishka Singh in Washington; Editing by Sandra Maler and Matthew Lewis)

By Kanishka Singh