Norway's government has collapsed over the decision to allow an ISIS bride to return to the country from Syria with her children.

The populist Progress Party pulled out of Norway's coalition government today after the mother was permitted repatriation so that her gravely ill five-year-old son could receive medical treatment.

The 29-year-old and her two children have been living in the Al-Hol camp in Syria - notorious in Britain as the detention centre which held Shamima Begum.

Prime Minister Erna Solberg said she would forge on with a minority government comprised of her Conservatives, the centrist Liberal Party and the Christian Democrats.

Prime Minister Erna Solberg, leader of the Conservative Party, speaks on Monday after the populist Progress Party said it would no longer support her government

The 29-year-old and her two children have been living in the Al-Hol camp in Syria - notorious in Britain as the detention centre which held Shamima Begum (pictured: file photo of women at the Al-Hol camp earlier this month)

Progress Party leader Siv Jensen said that 'the cup is now full' after the decision to allow the woman to return to Norway, on which her anti-immigration party feels it was not consulted.

She added that when Solberg's coalition expanded a year ago to include the liberals and the Christian Democrats, veering more to the centre and becoming a majority government, 'enthusiasm dropped.'

'Over time, politics was too much based on compromises,' said Jensen, who is Norway's outgoing finance minister.

Prime Minister Solberg said she 'understood' why the Progress Party wanted to leave her coalition government, adding she would seek cooperation with the party - which is Norway's third-largest.

Norway's next parliamentary election is scheduled for September 2021.

To stay in office until then and pass legislation in the 169-seat parliament, Solberg needs the support of parties outside the government, including the Progress Party.

The Norwegian woman of Pakistani descent reportedly travelled to Syria in 2013 and married a Norwegian foreign fighter there who was later killed in fighting.

She was formally arrested Saturday upon her return and was placed in an Oslo hospital with both children.

Jensen said many believed that the woman, who has not been named, 'used her child as a shield to come back to Norway.'

Norway's Progress party leader and Finance Minister Siv Jensen today, she had accused the woman as 'using her child as a shield to come back to Norway'

'There are many ... who are displeased by this, not just in the Progress Party,' Jensen said last week.

The mother, who was not named, refused to let the sick child travel alone to Norway, which then allowed her to travel from the Kurdish-controlled camp at Al-Hol where all three had been detained since March 2019.

'A majority in the government believed that concern for the child was paramount,' Solberg said.

Solberg has been prime minister of the Scandinavian country since 2013 when she formed a coalition with the Progress Party. The parties won renewed support in 2017 elections.

ISIS's new leader unmasked: Sharia law graduate Al-Salbi born into Iraqi Turkmen family is revealed as man now running the terror group after Abu Bakr al-Baghdadi fireball death in US strike

Two intelligence services said that al-Salbi took over from Abu Bakr al-Baghdadi

Al-Salbi, who helped found ISIS, brought in brutal Sharia Law in Iraq and Syria

Spies unmasked al-Salbi and paint a picture of extremist similar to al-Baghdadi

The new leader of Islamic State has been revealed as Iraqi Amir Mohammed Abdul Rahman al-Mawli al-Salbi.

Two intelligence services said al-Salbi took over from Abu Bakr al-Baghdadi after the terrorist leader blew himself up in October.

Al-Salbi, who helped found ISIS, brought in brutal Sharia Law in Iraq and Syria, led the enslavement of the Yazidi and has operated across the world.

The new leader of Islamic State has been revealed as Iraqi Amir Mohammed Abdul Rahman al-Mawli al-Salbi (pictured)

The terrorist was made leader just hours after al-Baghdadi died, despite his named being reported as Abu Ibrahim al-Hashimi al-Quraishi.

This was a nom de guerre and officials said they had heard little of the 'nobody' at the time.

Spies have unmasked al-Salbi over the past three months and paint a picture of a hardened extremist similar to al-Baghdadi, according to the Guardian.

The Mosul-born leader is believed to be one of the most influential ideologues left in ISIS's depleted ranks and is one of the last non-Arabs.

He was born in Tal Afar, a city near Mosul, to Iraqi Turkmen. After a background as an Islamic scholar, he rose the ranks in the terror organisation, and tried to justify an attempted genocide on the Yazidi people.

Two intelligence services said al-Salbi took over from Abu Bakr al-Baghdadi (pictured) after the terrorist leader blew himself up in October

As chief legislator al-Salbi made it so homosexuals were thrown off roofs and women accused of adultery were stoned.

He is also known as 'The Professor' and 'The Destroyer', and took over operations from al-Baghdadi from July after the leader struggled with his health.

They became friends while caged in US Camp Bucca detention centre, Iraq.

The Americans put a $5million bounty on al-Salbi's head - as well as two other senior terrorists - before al-Baghdadi died.

Al-Salbi claims he is a direct descendant from the Prophet Mohammed.

Al-Baghdadi was cornered by Delta Force commandos as they stormed his compound in the village of Barisha near Idlib, northern Syria, on October 26.

The extremist cleric blew himself up by detonating a suicide belt after running into a dead end and dragging two of his children with him to their deaths.

According to U.S. Secretary of State Mike Pompeo, two of Baghdadi's wives were killed in the assault.

The raid was a major blow to ISIS, which has lost territories it held in Syria and Iraq in a series of military defeats by the US-led coalition and Syrian and Iraqi allies.

Many IS members escaped through smuggling routes to north-western Syria in the final days of battle ahead of the group's territorial defeat earlier this year, while others have melted into the desert in Syria or Iraq.