Sweden reportedly is rethinking its centuries-old policy of military neutrality and could join NATO over fears of Russian aggression.

The Los Angeles Times reports that Swedish officials fear a resurgent Russia due to its increased air and naval patrols into the Baltic states’ airspace and maritime zones over the last two years. Such aggressive Russian measures have stoked new hostilities between the West and Moscow.

Sweden itself was put on edge in October of last year after navy and maritime security forces hunted for a suspected Russian submarine off the Stockholm archipelago. However, the hunt yielded no vessel.

After Russia’s annexation of Crimea from Ukraine last year, one in three Swedes now support Swedish membership in NATO, according to the newspaper.

Moscow's ambassador to Sweden, Viktor Tatarintsev, warned Stockholm that Moscow might react militarily should Sweden abandon its neutrality and join NATO. Sweden has remained neutral in armed conflicts, including World War II for more than 200 years.

"I don't think it will become relevant in the near future, even though there has been a certain swing in public opinion. But if it happens there will be counter measures," Tatarintsev told Swedish newspaper Dagens Nyheter in June. "Putin pointed out that there will be consequences, that Russia will have to resort to a response of the military kind and reorientate our troops and missiles. The country that joins NATO needs to be aware of the risks it is exposing itself to."

Another sign of support in Sweden for joining NATO came this week when the leader of a key opposition party in the country said she would advocate a move toward membership at the annual party conference.

Center Party leader Annie Loof wrote an opinion column in the Svenska Dagbladet, saying “Sweden cannot expect military support if we are not full members of the organization. We can no longer close our eyes to that.”

Sweden’s largest party – The Moderates – has already expressed its support for joining the alliance, as have the Liberals. The Christian Democrats plan to reevaluate the issue at its party conference in October, leader Ebba Busch Thor told the TT news agency.

Though Sweden’s ruling coalition of Social Democrats and Greens remain opposed to joining NATO, they have agreed to closer engagement with the Western defense alliance and recently joined a coalition with fellow Nordic countries Denmark, Norway, Iceland and Finland this past April.

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