German Chancellor Angela Merkel said there was a "glimmer of hope" that Ukraine could finally head towards a political solution to ending the separatist war in the country's east.
President Vladimir Putin called on the International Monetary Fund (IMF) to lend an additional $3 billion to Ukraine to help the ex-Soviet country pay off its debt to Russia.
Ukrainian Prime Minister Arseniy Yatsenyuk blamed Russia's security service for last year's downing of the MH17 airliner over pro-Kremlin separatist territory in the east of the ex-Soviet state.
Ukranian President Petro Poroshenko stressed the need for legitimate elections in the country's separatist regions in order to eventually re-integrate the pro-Moscow strongholds.
President Petro Poroshenko said a "real truce" had begun in Ukraine but that a long-lasting peace with pro-Russian insurgents would still take some time.
Hundreds of pro-Kiev activists from Crimea's Tatar community launched a blockade of roads from Ukraine to the Crimean peninsula to protest Russia's seizure of their home region.
Ukrainian President Petro Poroshenko expanded a list of sanctions against Russian companies and individuals held responsible for the ex-Soviet state's eastern uprising and for Moscow's annexation of Crimea.
Billionaire mogul and White House frontrunner Donald Trump accused US President Barack Obama of paying "lip service" on Ukraine and failing to stand up to Russian strongman Vladimir Putin.
Ukrainian President Petro Poroshenko accused Russia of challenging the "entire democratic world" by annexing Crimea and allegedly arming separatist rebels in the east of his ex-Soviet state.
Ukrainian Prime Minister Arseniy Yatsenyuk criticised as "anti-Ukrainian and anti-European" a deal between Russia's energy giant Gazprom and several Western firms to build a second gas pipeline under the Baltic Sea.
Ukrainian Prime Minister Arseniy Yatsenyuk warned that any attempt to hold "unlawful" elections in rebel-run areas in the country's east would constitute a breach of a February peace deal.
EU foreign policy chief Federica Mogherini expressed concern over "very worrying" deadly clashes in Kiev as Ukrainian lawmakers backed an autonomy plan for rebel regions.
Ukrainian President Petro Poroshenko said those behind deadly Kiev clashes that erupted after a vote on autonomy for separatist eastern regions deserved severe punishment.
Anya wasn't even born when Chernobyl exploded nearly 30 years ago, but even today its radioactive fallout stalks her and other Ukrainian youngsters growing up near the disused plant.
A Dutch lecturer accused a top university in Kazakhstan of sacking him after he tried to hold a talk on the "Russian-Ukrainian conflict", a claim denied by the university.
The EU sharply criticised Russia on Tuesday for the jailing of Ukrainian filmmaker and Kremlin critic Oleg Sentsov, calling it a violation of international law.