THE HAGUE, July 14 (Reuters) - The United States and more than 40 other countries agreed on Thursday (Jul 14) to coordinate investigations into suspected war crimes in Ukraine, shortly after what Kyiv said was a Russian missile strike that killed civilians far from front lines.

Ukrainian President Volodymyr Zelenskyy told the international conference that Russian missiles had struck two community centres in the west of Ukraine, killing 20 people, including three children, and wounding many more.

Russia has repeatedly denied involvement in war crimes and deliberately targeting civilians since it invaded Ukraine in February. It says it launched a "special military operation" to protect Russian speakers and root out dangerous nationalists. Ukraine says Moscow is waging an unprovoked war of conquest.

"Today in the morning, Russian missiles hit our city of Vinnytsia, an ordinary, peaceful city. Cruise missiles hit two community facilities, houses were destroyed, a medical centre was destroyed, cars and trams were (set) on fire," Zelenskiy said by video link. "This is the act of Russian terror."

The Russian defence ministry did not immediately comment on the reports from Vinnytsia.

On Thursday, 45 countries at the conference in The Hague - headquarters of the International Criminal Court (ICC) - signed a political declaration to work together on investigations into war crimes in Ukraine.

Those countries included European Union states as well as Britain, the United States, Canada, Mexico and Australia.

They also pledged €20 million (US$20 million) to assist the ICC, as well as the prosecutor general's office in Ukraine and United Nations support efforts.

With some 23,000 war crimes investigations now open and different countries heading teams, evidence needs to be credible and organised, officials said.

Separately, Dutch Foreign Minister Wopke Hoekstra said the Netherlands would also consider setting up a special international Ukraine war crimes tribunal, in part because neither Ukraine nor Russia are members of the ICC.

"We have to fill a vacuum and the ICC here doesn't have the jurisdictions so I can imagine we do look into coming up with such a tribunal ... We will take a look into this," he said.