The online dictionary will contain around 15,000 Belarusian words and their Lithuanian translations as well as examples of common usage and information on grammar and stylistics. The publication is scheduled for 2014.
"A bilingual Lithuanian-Belarusian dictionary will be very useful for Lithuania's Belarusian community and Lithuanians living in Belarus, as well as philologists, translators, and everyone who is interested in the culture, history, and traditions of both countries," the government said in a statement.
Belarusians are the third largest ethnic minority in Lithuania after Poles and Russians.
Relations between the Lithuanian and Belarusians languages were actively researched in the 1970s and 1980s but no professional textbooks or dictionaries have been published so far.
There are two official languages in Belarus – Belarusian and Russian.