European Union leaders are set to meet with their counterparts from six eastern countries in Riga on May 21 and 22, amid concern that the meeting could further inflame tensions with Russia.
The main question at the two-day meeting in the Latvian capital 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, eventually led to 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.
On May 19, Russian Foreign Minister Sergei Lavrov warned the EU during a trip to Brussels against taking steps that could harm Russian interests, adding that the bloc's relations with its eastern neighbors must not have negative consequences for Moscow.
Still, he seemed more conciliatory about the EU forging a landmark trade deal with Ukraine starting next year.
The partnership program aims to encourage the six former Soviet states to undertake reforms in return for closer relations and economic benefits.
Brussels insists its policy is not aimed at creating dividing lines in Europe, but Moscow has expressed strong misgivings, arguing that closer economic ties between the EU and its main trading partners could harm Russia.
Since the 2013 summit, Kyiv's new leadership has signed up to closer political and economic relations with the EU, as have Georgia and Moldova.
But Belarus and Azerbaijan have shown little interest in following that path, while Armenia has joined the Russia-backed Eurasian Economic Union.
Few concrete outcomes are likely from the talks, at which 25 of the EU's 28 leaders are expected as well as the presidents or prime ministers of all Eastern Partnership countries.
Ukraine is due to sign a previously agreed 1.8 billion euro ($2 billion) EU loan deal, while the European Commission will offer funding for small and medium-sized companies in Georgia, Moldova, and Ukraine.
Ukraine and Georgia are likely to be disappointed at not being offered visa-free travel to the EU.
"If we fail to show progress on issues such as visa liberalization, it would amount to accepting an absurd logic that making it easier for a Georgian tourist to visit Paris is a threat to Russia," Georgian President Giorgi Margvelashvili warned in Tbilisi ahead of the summit.
"Top EU leaders gave me clear assurances that there is no informal Russian veto on Georgia's free choice to be part of Europe," Margvelashvili told AFP in an interview.
"But unfortunately, Russia -- with the aggression against Ukraine -- has managed to temporarily dent the Eastern Partnership agenda, shifting it towards confrontation," he added.