More than 40 European leaders will meet in Moldova on Thursday in a show of support for the former Soviet republic and neighboring Ukraine as Kyiv prepares to launch a counteroffensive against occupying Russian forces.

The gathering of the EU's 27 member states and 20 other European countries at a castle deep in Moldovan wine country will touch on a range of strategic issues and launch a new EU partnership mission in the country. But the focus will be on a symbolic show of unity on Ukraine's doorstep.

"If you sit in Moscow and see 47 countries in your immediate or close neighborhood meeting together, that's an important message," an EU official told reporters ahead of the summit, which takes place 40 km southeast of the capital Chisinau.