VIENNA - The Austria's army will on Wednesday start carrying out thorough identity and bag checks of every migrant arriving at the main border crossing with Slovenia, as part of new government measures heralding a tougher stance in Europe's refugee crisis.

Some 500 newly deployed troops will assist police in processing up to 6,000 migrants on a daily basis at the Spielfeld crossing in the southern state of Styria, police spokesman Fritz Grundnig told AFP on Tuesday. In case of a spike in numbers, security forces could handle as many as 11,000 people - roughly the average daily number of migrants who crossed into Austria late last year.

‘Until now we've only been able to carry out random spot checks but this will allow us to ensure watertight controls of every single migrant,’ Grundnig said. Initially the soldiers would only process ‘several hundred migrants’ while the rest would be allowed to cross from Slovenia via Austria's other border crossing in Carinthia state.

‘But the idea is that eventually Spielfeld will be the only crossing point for migrants,’ Grundnig added. The new measure comes just days before Austria is expected to complete the construction of a 3.7-kilometre (2.3-mile) mesh fence at Spielfeld.

The barrier - which could be ready by Friday, according to Grundnig - will be the first of its kind inside the EU's passport-free Schengen zone. In a further sign of its hardening line, Austria has signalled that it would follow neighbouring Germany's lead and begin turning back any new arrivals seeking to claim asylum in Scandinavia.

Berlin's clampdown started after Sweden and Denmark tightened their borders in early January. ‘If Germany rejects migrants who want to travel to Sweden, we will do the same,’ Austrian Chancellor Werner Faymann said Sunday. Austria, a small nation of 8.5 million people, has become a key transit country for hundreds of thousands of migrants and refugees entering the European Union.

Although most travel onwards, some 90,000 requested asylum in Austria in 2015. The influx has sparked tensions within the ruling centrist coalition between Faymann's Social Democrats (SPOe) and the conservative OeVP party. Although Faymann has noticeably sharpened his tone and called for ‘tougher controls’ in recent weeks, he has so far resisted joining the OeVP's demand to cap migrant numbers. The government will debate the situation at a national asylum summit on Wednesday.

Moreover, around 40 rebels from German Chancellor Angela Merkel's conservative party sent her a letter Tuesday demanding an about-face on her liberal refugee policy. Seizing on slipping poll numbers and mounting scepticism among Germans about the country's ability to handle the influx, which brought nearly 1.1 million newcomers last year, the Christian Democratic Union (CDU) lawmakers said Merkel must face up to reality.

‘In light of the developments in recent months, we can no longer speak of a great challenge - we are on the verge of our country being overwhelmed,’ they wrote, in the letter addressed ‘Dear Madam Chancellor’ and obtained by AFP.

The appeal by about 40 deputies marked the largest single expression of dissent by members of Merkel's own camp since the refugee crisis hit Germany in September. The CDU has 256 seats in the Bundestag lower house of parliament.

‘We do not want to divide the CDU parliamentary group - we are only asking for the law to be applied,’ one of the initiators of the letter, Christian von Stetten, told AFP. The deputies said that quick processing of asylum applications, housing in ‘appropriate’ conditions and ‘successful’ integration of newcomers were all impossible if ‘the number of arrivals remains this high or begins to climb again in the spring’.

They urged Germany to resume applying the EU's Dublin asylum regulations, which say that refugees must seek asylum in the first member country that they land in. Merkel, who has attempted to rally Germans with the slogan ‘We can do it’, has pledged a ‘tangible reduction’ in the number of asylum seekers arriving in Germany in the coming months.

This would entail a raft of new measures at the national level and in cooperation with EU partners and neighbours of war-ravaged Syria, from which around 40 percent of last year's new arrivals came. But she has steadfastly rebuffed calls to close the German border, saying it would be unconstitutional and ultimately ineffective.

Time is running out to turn the tide ahead of three key state elections coming up in March, when the right-wing populist Alternative for Germany party hopes to gain seats at the CDU's expense. The public mood has soured in particular since a rash of sexual assaults and robberies during New Year's Eve celebrations in the western city of Cologne blamed on North African and Arab migrants.