They are scheduled to meet with Lithuanian President Gitanas Nauseda on Sunday, the presidential office said.
The security situation in the region will be discussed with the NATO and EC leaders as well as the existing situation at the EU-Belarusian border, caused by the Lukashenko regime's ongoing hybrid attack.
Kristina Belikova, a representative of the presidential office, told BNS the NATO and EC chiefs will pay a one-day visit to Lithuania on Sunday, adding that a press conference is being planned and a more detailed visit program is now being coordinated.
Almost 4,200 irregular migrants have crossed into Lithuania from Belarus illegally so far this year, forcing Lithuania to declare a state of emergency earlier this month.
Vilnius accuses the Minsk regime of orchestrating the unprecedented migration influx, calling it "hybrid aggression".