U.S. Vice President Joe Biden told Ukrainian presidential candidates and members of parliament on Tuesday that Washington was ready to help Ukraine's economy but warned them they must fight the "cancer" of endemic corruption.
In Kiev to offer a symbolic show of U.S. support, Biden said the presidential election on May 25 would be an opportunity to lay the groundwork for a more unified and prosperous country.
Washington, he said, was ready to assist in holding it.
"You're a month away from what I would respectfully suggest ... may be the most important election in Ukrainian history," Biden said during a meeting at the parliament building.
Biden's visit to Ukraine follows the signing in Geneva last Thursday of a four-way peace deal to de-escalate tension in eastern Ukraine where pro-Russian separatists have seized towns and key facilities.
The Kiev leadership says the rebellions in the east are inspired and directed by Russia, one of the signatories of the Geneva accord, which annexed Crimea in March.
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The Geneva accord is having only limited effect, however, with separatists refusing to put down their arms and pull out of key occupied points in line with the agreement.