The Social Democrat politician visited the island of Gotland this week to inspect the country’s military forces which were deployed in September last year.
Army bosses ordered 150 soldiers and tanks to the southern island off the Swedish coast urgently after Russia reportedly made a serious threat to national security.
Speaking to Aftonbladet, Mr Löfven said: “We want to send a signal to anyone who is thinking about attacking our territories that it will be a painful [affair].
“We are determined to defend Swedish territory, that includes defending Gotland island. That is why we are strengthening our defence capability.”
Stefan Löfven inspected Swedish armed forces on Gotland island
Swedish military has carried out a series of drills since September with anti-ship missiles to ward off any potential aggression towards the Nato ally.
Backing up the Swedish PM’s statement, defence minister Peter Hultqvist said their military presence on the island sent a strong message.
He said: “What we are doing in Gotland, and that we are allocating extra money in the spring budget, is a clear signal that Sweden has an ambition of defending the island.
“We recognise Gotland has a strategic value and that whoever is in control of the island also has control over the sea and airways in relation to the Baltics. Gotland is also important for Finland and the Swedish mainland.”
We are determined to defend Swedish territory, that includes defending Gotland island
Sweden’s coastal defences were disbanded in 2000, but as global tensions are increasing yet again it was decided the Nordic nation needed to bolster up its border defences to ward off potential enemies of the state.
Late last year footage emerged to Swedish armed forces carrying out drills with Saab Robotsystem 15 (RBS-15) anti-ship missiles.
The artillery was brought out of retirement along with several Scania trucks, after being kept on display at a local museum since the end of the Cold War.
Mr Hultqvist said: "It is extremely good that we have land-based coastal missile systems back in our national defence.
11 things you need to know about NATO
Tue, February 14, 2017
NATO – The North Atlantic Treaty Organization is an intergovernmental military alliance based on the North Atlantic Treaty which was signed on 4th April 1949. The organization constitutes a system of collective defence whereby its member states agree to mutual defence in response to an attack by any external party.
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Every member country, no matter how large or small, has an equal say in discussions and decisions. Photo shows: Signing the North Atlantic Treaty which marked the beginning of NATO, 1949.
"It means that we can shoot anti-ship missiles from land over great distance.
"It provides increased flexibility and capability in marine warfare. It increases military capability, and that's something we need.”
The decision to strengthen Sweden’s military capability came after Nato last year uncovered the Russian military had conducted a nuclear strike against Sweden during a series of war games.
In a Nato report for 2015, Russian jets, during a dummy nuclear attack, approached Swedish airspace and conducted the mock strike.
As Jens Stoltenberg, the secretary general of Nato, disclosed the disturbing information, leaked documents from army chief Anders Brannstrom before a meeting with Swedish defence management said war with Russia could hit the country in a few years.
The report claimed Sweden should be ready for “armed battle against a qualified opponent” after more than 200 years of peace.
Mr Brannstrom said: "The security situation we are currently experiencing leads me to the conclusion that in the course of a few years we might be at war."