Sweden, one of the world's most liberal countries, on Thursday moved to make it illegal to join a terror organisation as the government seeks to punish jihadist fighters returning home.
The new law, set to enter into force in August, "will allow us to prosecute and try many more of them than we've been able to until now," Justice Minister Morgan Johansson said.
However, the legislation will not be retroactive and therefore cannot be applied to the dozens of fighters who have already come back to Sweden.
The centre-left government tightened its anti-terror laws following a deadly 2017 truck attack carried out by an Uzbek asylum-seeker.
Under the current laws, Sweden can only prosecute foreign fighters if it can prove that they have been involved in crimes violating the Geneva Convention.
Some 300 Swedish nationals have joined jihadist groups like the Islamic State in Syria and Iraq since 2012, according to the security services.
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Around half have since returned while another 100 are still in the conflict zone and 50 were killed, the authorities say.
Under the proposed changes, it will become illegal to be part of, assist or recruit for proscribed terror organisations.
The offences will be punishable by up to six years in prison, the government said Thursday.
In addition, sentences will be tightened for those leaving Sweden to fight abroad and for the financing of terror organisations.
The far-right Sweden Democrats (SD), who came third in September elections, said the proposed toughening of anti-terror laws came too late and were too lenient.
"All those who left to fight alongside the Islamic State group were welcomed with open arms in Sweden to live here as citizens exonerated from all criminal responsibility," SD lawmaker Adam Marttinen told the Dagens Nyheter newspaper.