It depends on the plan you buy, and it is worth checking rather than assuming. The two countries are neighbours but they are not always in the same regional bundle — some "Caucasus" and "Europe" plans include one and not the other.
Two workable approaches. Buy a regional plan whose country list explicitly names both, or buy a single-country plan for each. For a trip covering only these two, two single-country plans are often cheaper than a broad regional plan you will barely use.
Whatever you buy, check the coverage list before paying — the plan name is not a reliable guide to what is actually covered.