German Chancellor Angela Merkel has said she regrets nothing about her response to the migrant crisis of 2015.

More than a million people from across Asia, Africa, Europe and the Middle East entered Germany two years ago after Mrs Merkel opened her country's doors to Syrian refugees.

Her party's support dropped as a consequence and led to a surge in support for the right-wing Alternative for Germany (AfD) party, which pollsters say could win up to 10 percent in the September election.

But in an interview with the Welt am Sonntag newspaper, the chancellor said she would do everything 'the same way again' if she had the opportunity.

No regrets: German Chancellor Angela Merkel has said she would change nothing about her response to the migrant crisis of 2015

'I'd make all the important decisions of 2015 the same way again,' Merkel said.

'It was an extraordinary situation and I made my decision based on what I thought was right from a political and humanitarian standpoint.

'Those kinds of extraordinary situations happen every once in a while in a country's history,' she added. 'The head of government has to act and I did.'

She also attacked EU countries that refused to accept migrants as part of a redistribution plan, explaining that such behaviour is 'not on'.

'That contradicts the spirit of Europe,' she said. 'We'll overcome that.

'It will take time and patience but we will succeed.'

Influx: More than a million people from across Asia, Africa, Europe and the Middle East entered Germany two years ago after Mrs Merkel opened her country's doors to Syrian refugees

Decider: Mrs Merkel said it 'was an extraordinary situation and I made my decision based on what I thought was right from a political and humanitarian standpoint'

Four weeks before the September 24 election, an Emnid opinion poll showed Merkel's conservatives would win 38 per cent, or 15 points ahead of the center-left Social Democrats (SPD).

That is up from 32 per cent in February but well below the 41.5 percent her party won in the last election in 2013.

Merkel, seeing a fourth term, has had to contend with loud and sustained heckling from demonstrators strongly opposed to her refugee policies so far on the campaign trail.

Pictured left: A man holds up a sign reading 'No violence against women' as he takes part in a demonstration in front of the cathedral in Cologne. On New Year's Eve 2015, there were sex attacks by migrants in the city. Pictured right: A long line of migrants in Hungary on the journey north during 2015

The volume and intensity of the protests have been especially strong in her home region in formerly communist eastern Germany.

But the 63-year-chancellor said she would not be kept away from areas where animosity towards her runs high.

'We're a democracy and everyone can freely express themselves in public the way they want,' she said. 'It's important that we don't go out of our way to avoid certain areas only because there are a bunch of people screaming.'

Her party's support dropped as a consequence and led to a surge in support for the right-wing Alternative for Germany (AfD) party, which pollsters say could win up to 10 percent in the September election. Pictured: AfD candidates and supporters react to the first predictions in the Rhineland-Palatinate state parliamentary elections in March 2016

Support for Merkel and her party has recovered somewhat after the influx of refugees slowed in 2016 to 280,000 and fell even further to about 106,000 in the first seven months of this year.

Merkel said it was unfair that Greece and Italy were left on their own carrying the full burden of the refugee crisis 'simply because of their geography'.

She added she would not stop pushing for a distribution of refugees across the European Union.