"We should look back calmly at what we have done in recent years to improve the immigration rules," Merkel said. "Then we can decide if it needs further improvement."

Members of parliament from Merkel's conservative Christian Democratic Union (CDU) and their Bavaria-based associate party, the Christian Social Union (CSU), had rejected changes to the nation's immigration rules.

That includes Interior Minister Thomas de Maiziere, who has repeatedly ruled out introducing a new immigration law.

However, CDU general secretary Peter Tauber has joined the Social Democratic Party (SPD), the junior member of Merkel's coalition government, and the opposition Green Party in calling for immigration reforms.

The centre-left SPD plans to unveil a position paper by the end of the month that is expected to urge the government to introduce a points system to attract qualified immigrants.

But the chancellor said Tuesday that she had not reached any conclusion on whether the immigration laws need reforming.

SPD parliamentary leader Thomas Oppermann welcomed the chancellor's comments on reviewing existing laws, saying he was pleased that "the immigration debate in Germany had gathered momentum."

Oppermann plans to travel to Canada next week to examine the nation's immigration system, looking specifically at how the system helps address labour shortages that the domestic jobs market is unable to fill.

"I am still convinced that a good way could be a flexible point system," he said.

Immigration re-emerged as an issue in Germany after a recent push for measures to control a migrant influx spearheaded by two populist right-wing groups: the Alternative for Germany (AfD) and the anti-Islamist movement Pegida.

The AfD has been chipping away at support for the major political parties, including the CDU, with opinion polls showing that the AfD could enter the nation's parliament at the next election in 2017.

It faces a major test of its political strength this month at regional elections in the northern German city state of Hamburg.

The AfD appeared on the national stage in 2013 as a eurosceptic party and later launched a campaign questioning the nation's immigration laws - a platform that helped pave the way for the party to gain parliamentary seats in three eastern states.

This coincided with the launch in October of Pegida's anti-Islamist and anti-refugee movement in the eastern city of Dresden. Pegida also called for a radical rethink of the country's immigration laws.

Carsten Sieling, a member of the SPD's left wing, said he also sees Canada as a potential model for coping with an influx of migrants.

"Germany does not need a bouncer mentality like the CSU wants it to have," Sieling said.

In Canada, authorities use a point system to fill gaps in the labour market by awarding points to would-be immigrants depending on their job qualifications and language skills.

The decline in Germany's birth rate adds pressure on Merkel's government to consider reforming immigration rules with Sieling saying that a new law could be cast "as a law to secure the future."

Still, the debate must also address the question of whether Germany would be prepared to attract new immigrants by liberalizing its strict citizenship laws.

Like many Western nations, Germany has job shortages in a range of sectors, including the information-technology industry as well as the health system.

The German Chamber of Commerce and Industry estimated that the nation needs 100,000 to 150,000 additional foreign workers each year to fill the gaps in the workforce.

However, the chamber is not pressing for changes to the present law to address gaps in the labour market. The group's managing director, Martin Wansleben, pointed out that most of Germany's immigrants are from the European Union and have free movement of travel in the EU.

"Above all, we need a better welcoming culture," Wansleben said.