The maximum prison sentence for treason in Denmark currently stands at 16 years.
Per capita, Denmark has become the second biggest European country of origin for jihadist fighters, after Belgium, going to fight in Iraq and Syria.
Intended legislation is directed at protecting general national security and those Danish military forces engaged in fighting militant Islamic groups in the Middle East, said Søren Pind, Denmark's justice minister.
"Denmark is now one of the countries that produces the most radicalized persons fighting in Syria. This is a situation we are taking very seriously," Pind said.
Peter Christensen, who replaced Carl Holst as defence minister on Sept. 30, will oversee the broadening of the military's intelligence-gathering resources both in Denmark and abroad, including specialized Danish forces operating overseas.
The primary focus will be militant Islamic groups, with additional funds being made available to military and national security agencies to better monitor radicalized Danes traveling abroad to fight with the Islamic State group.
"We need a higher level of security to protect all of our national interests. Any persons leaving Denmark to join ISIS and fight against Danish soldiers are committing treason," Mette Frederiksen, a former minister for justice and leader of the Social Democratic Party, said, using an acronym for the Islamic State group.
Under existing Danish legislation, radicalized fighters from Denmark can only be convicted if they are caught and charged with attacking Danish forces, or if they assist the enemy in battle against Danish forces.
"We intend to send our F-16s back to Iraq. ISIS needs to be fought and Denmark must carry its share of the load," Kristian Jensen, Denmark's foreign minister, said.
Denmark, which has also provided 120 military instructors to support the US training mission targeting the Iraqi Army, is expected to send a similarly sized fresh F-16 squadron to Iraq no later than June 2016.
The bill for direct Danish action against ISIS is expected to run close to $100 million in 2014. This includes the cost of maintaining its F-16 squadron and 90-man crew in Iraq.
The F-16 squadron had documented operating costs of almost US$34 million during the four month term to February 2015. During this period, Danish F-16s dropped an estimated 200 bombs in 200 missions. Munitions costs over the four months in question amounted to US$6.8 million.
Moreover, costs associated with Danish forces' operations in Afghanistan in 2001-2012 are estimated at over US$2 billion. Danish military operations costs in Iraq in 2003-2007, meanwhile, ran to around US$363 million, while the costs attached to Danish operations in Libya in 2011 amounted to almost US$100 million.
Denmark's Nordic neighbor Sweden is considering drafting legislation to make it unlawful for citizens to fight in armed conflicts alongside terrorist organizations such as ISIS.
"It is completely unacceptable that citizens of Sweden are leaving the country to either join ISIS, help finance this organization or fight for it," Justice Minister Morgan Johansson said.
The Justice Ministry plans to present draft legislation to the government in June 2016. The action forms part of tougher initiatives to stem the flow of foreign jihadists into Sweden.
Intelligence from Säpo, Sweden's national security service, estimates that over 40 radicalized Swedes, out of a total number of 150, have died fighting for ISIS against coalition forces in Syria and Iraq since 2010.
Sweden is committed to sending up to 120 troops to northern Iraq to train Iraqi and Kurdish Peshmerga fighters as part of the US-led coalition against ISIS. The specialized Swedish troops will be under US command.