Senior officials from the United States, Russia, Ukraine, and the European Union are set to meet for talks on the Ukraine crisis.
The meeting in Geneva comes with pro-Russian separatists gaining ground in several cities and towns in eastern Ukraine.
Arriving in Geneva, Ukraine's acting Foreign Minister Andriy Deshchystsya said he would demand Moscow stop supporting "terrorist activities" in his country and pull back its troops from the border.
Deshchystsya said Kyiv was willing to talk to Moscow, but stressed Russia had no right to dictate to Ukraine how to run the country.
Russian President Vladimir Putin is scheduled to speak on April 17 at an annual question-and-answer session with citizens, which analysts say could signal how far he intends to go in Ukraine.
Kyiv says the uprising is basically the same as the seizure of Crimea, where armed pro-Russian partisans also occupied buildings, declared independence, and proclaimed themselves in charge of state bodies.
Quoted by AP, a senior U.S. official said Ukrainian diplomats planned to brief Russian Foreign Minister Sergei Lavrov about efforts to decentralize power in Ukraine and protect Russian-speaking minorities like the ones living in eastern Ukraine, key demands of the Kremlin.
U.S. officials quoted by Reuters say Washington does not expect any breakthrough at the Geneva meeting, which is also being attended by U.S. Secretary of State John Kerry.
U.S. diplomats say if no progress is made in Geneva, the United States is likely to impose a further round of sanctions against Russia.
In an interview on U.S. television, President Barack Obama said each time Russia took steps to destabilize Ukraine, there would be consequences.
According to AP, officials already have prepared targets for sanctions that include wealthy individuals close to Putin and the businesses they run.
The Obama administration is also said to be working on a package of nonlethal assistance for Ukraine's military.
On April 16, Ukrainian forces suffered another setback in efforts to regain control in the east.
In the town of Kramatorsk, insurgents commandeered six Ukrainian armored vehicles and raised the Russian flag.
Separatists also stormed the city administration building in Donetsk.
A pro-Russian mob also tried to storm a Ukrainian military base near the eastern city of Mariupol.
On April 16, NATO announced urgent new steps to reinforce security on its eastern borders.
"You will see deployments at sea, in the air, on land, to take place immediately. That means within days," NATO Secretary-General Anders Fogh Rasmussen told a news conference after meeting of ambassadors from the 28-member alliance in Brussels.
With reporting by AP, Reuters, and AFP