Russia Prime Minister Vladimir Putin has warned of ending military technology cooperation with Ukraine if it joins the North Atlantic Treaty Organization, or NATO.
Putin made the comment when meeting with his Ukrainian counterpart Yulia Tymoshenko in Moscow.
"As for sensitive technologies, and first of all high-tech rocket technologies, and some other modern military technologies, we will think beforehand in this case (on Ukraine joining NATO) on how to move them, despite any financial expenses for Russia."
Ukraine has a massive arms and electronics industry inherited from the Soviet era that relies on contracts with Russia's military and space agencies.
Moscow vehemently opposes efforts by Ukraine to gain NATO membership, saying it's destructive and will ruin the Russian-Ukrainian relations.
But Tymoshenko stressed decisions will be made based on public opinion.
"As for the joining of Ukraine to NATO, I want firmly assure that basic point for us will be the opinion of the Ukrainian people."
The two sides appeared to have settled price disputes over natural gas supplies as Putin said Ukraine has paid its debt for Russian gas.
But Putin noted that next year Russia's state-owned gas monopoly Gazprom would more than double its gas price following a hike in prices for gas from Central Asian republics.
Ukraine mostly buys Central Asian gas, which is delivered through Gazprom-controlled pipelines crossing Russia.