"I don't see Russia as a direct threat to the Baltic states at the moment. The Pentagon and NATO don't see it either," he said.
"Believe me, based on my experience, my communication in Washington and elsewhere, the Kremlin is aware of red lines; we are behind the red lines."
The former long-time diplomat said that if elected Lithuania's president, he would increase defense spending, but would not call Russia a threat and a terrorist state.
"What would I change? I'd invest more in defense. I wouldn't call Russia a threat, as Ingrida has said in an interview, I wouldn’t liken Russia to (...) a terrorist state, calling all Russians terrorists. No doubt, I'd invest in Russia's democratic future. Processes do change (and) Putin won't stay (in power) forever. Therefore, we need to maintain the bridges Pope Francis spoke about," he said.
Ušackas said currently there is no risk of Russia starting war against Lithuania.
"There is a risk that, due to human error, a plane will crash, like it happened in Sakiai in 2005, or when tanks crossed into Lithuania from Belarus. The question then is whether there is liaison to ensure that this accident doesn't turn into a tragedy or a military conflict," he said.
In response to his criticism, Šimonytė noted that the US identified Russia as a threat in its 2016 security strategy, adding that she supports that position and does not think that Russia's behavior may change in the near future.
"If someone tries to keep redrawing those rules, if we have a situation where (two) persons play chess and a third person comes, takes the chessboard and hits these persons over the heads with it, then, obviously, it's very hard to speak about normal dialogue," the lawmaker said.
"If we say that we are all misunderstandings: two tourists poisoned someone (and) someone accidentally downed a plane using a BUK (missile) that came nobody knows from where. What about the occupation of Crimea, is there a human factor?", she asked.
Ušackas hit back by saying, "Do you really believe that Russia would attack a NATO member state now? Why did we join NATO? Because we believe in collective defense guarantees."
"But we have to all we can so as not to create the preconditions for a military conflict here," he added.
Ušackas will run against Šimonytė in the HU-LCD primaries to be held on November 3-4 to select the conservative party's candidate in next May's president election.
The latest opinion polls show that both politicians have at least 10 percent support among voters.
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