WASHINGTON, April 5 (Reuters) - The United States and its allies will on Wednesday impose new sanctions on Russian banks and officials and ban new investment in Russia, the White House said, after officials in Washington and Kyiv accused Moscow of committing war crimes in the Ukrainian town of Bucha.

The sanctions will increase curbs on financial institutions and state-owned enterprises in Russia and target Russian government officials and their families, White House press secretary Jen Psaki told reporters on Tuesday.

"Tomorrow, what we're going to announce... in coordination with the G7 and EU, (is) an additional sweeping package of sanctions measures that will impose costs on Russia and send it further down the road of economic, financial and technological isolation," Psaki said, noting that the G7 and EU comprised around 50% of the global economy.

The measures will "degrade key instruments of Russian state power, impose acute and immediate economic harm on Russia, and hold accountable the Russian kleptocracy that funds and supports (Russian President Vladimir) Putin's war," she said.

She declined to comment on reports that the sanctions would target the daughters of Putin.