Migrant crisis: Unity eludes EU on relocation
EU ministers meeting in Brussels have failed to agree unanimously on a plan to relocate 120,000 asylum seekers with mandatory quotas.
Instead, a majority agreed in principle and negotiations will now take place ahead of another meeting in October.
Earlier, more European countries introduced temporary border checks, hours after Germany imposed controls on its border with Austria.
And tough new border controls have now come into force in Hungary.
On Monday, police in Hungary completed a fence designed to stop thousands of migrants who have been crossing the border from Serbia.
The new laws, which came into effect at midnight (10:00 GMT), allow police deployed along the border to arrest anyone considered an illegal immigrant or who tries to breach the new fence.
'Time of the essence'
Luxembourg, which holds the EU presidency, said it was hoped that the relocation proposal - unveiled last week by European Commission chief Jean-Claude Juncker - could be made law at a meeting on 8 October.
Leading up to Monday's meeting, the Czech Republic, Slovakia and Hungary were among the nations opposed to mandatory quotas.
"The quota system isn't the solution," Slovak Interior Minister Robert Kalinak said as he arrived.
At a news conference after the talks, Luxembourg Foreign Minister Jean Asselborn said "not everyone is on board at the moment".
He warned the situation in Europe was "urgent and dramatic and time is of the essence".
Ministers did, however, agree to begin the relocation of 40,000 migrants from Greece and Italy to other EU states, as proposed by the European Commission before the summer.
Analysis: Chris Morris, BBC News, Brussels
After a difficult meeting marked by heated debate, there was no unanimous agreement on the proposal to relocate another 120,000 refugees across the EU - with mandatory quotas for individual member states.
The idea was to take the strain off countries like Greece and Italy, where most refugees first arrive. A clear majority of countries did agree to the proposal in principle, and that would be enough to push it through if necessary, against the wishes of countries like Hungary, Slovakia and the Czech Republic that remain opposed. For now though, there will be further talks in the hope of maintaining unity, at a time when many of the core values of the European Union are being put under close scrutiny.
EU ministers also agreed to push ahead with robust measures to process new arrivals more quickly and efficiently, and send home those whose asylum applications are rejected. But critics will be disappointed that more decisive action was not taken, given the scale of the crisis confronting Europe.
Under complex EU rules, a unanimous vote is not required and decisions can be made with a qualified majority.
However, correspondents says that would be a show of disunity that the EU is trying to avoid.
Mr Asselborn said a list of safe countries, to which failed asylum seekers can be returned, had been agreed on principle. He said Turkey would not be on the list because of an upsurge of violence between the government and Kurdish militants.
Austria deploys troops
Earlier, German Vice-Chancellor Sigmar Gabriel said its border checks, announced on Sunday, were a signal that Germany "cannot accommodate all of the refugees alone".
Austria, Slovakia and the Netherlands later said they would also tighten controls.
The moves are a challenge to the EU's Schengen agreement on free movement, although the rules do allow for temporary controls in emergencies.
European states have been struggling to cope with a record influx of migrants, who are mainly trying to reach Germany and Sweden.
Austrian police said up to 7,000 people had arrived from Hungary on Monday, and 14,000 on Sunday.
Chancellor Werner Faymann said troops were also being deployed, mainly to provide humanitarian help within Austria, but would be sent to the border if necessary.
"If Germany carries out border controls, Austria must put strengthened border controls in place," Vice-Chancellor Reinhold Mitterlehner said.
Most of the migrants who have moved north into Hungary in recent weeks have fled conflict, oppression and poverty in Syria, Iraq, Afghanistan and Eritrea.
Many have been refusing to register in Greece or Hungary, fearing it will stop them being granted asylum in Germany or other EU states.
Earlier on Monday, the UN refugee agency warned that refugees could find themselves "in legal limbo"
It said announcements of different border control measures by European states "only underlines the urgency of establishing a comprehensive European response".