European Union leaders are gathering in the Latvian capital, Riga, on May 21 for a summit with their counterparts from six eastern countries.
The number one question at the two-day meeting will be how the 28-member EU should reconcile its Eastern Partnership Program -- involving Armenia, Azerbaijan, Belarus, Georgia, Moldova and Ukraine -- with its relations to Russia.
Their last meeting, held in Vilnius in 2013, triggered the current crisis in Ukraine, after the country's former president Viktor Yanukovych backed out of a deal on closer ties with the European Union.
Months later, violent protests forced Yanukovych out of office. Tensions flared up in the east of the country, where a pro-Russian insurgency took hold.
Russia annexed the Crimean peninsula, leading to widespread condemnation and Western sanctions as relations soured.
Russia will be watching this week's summit closely. Foreign Minister Sergei Lavrov has warned the EU against taking steps that could harm Russian interests.