BERLIN (AP) – Germany planned to close its border with Austria and turn back asylum seekers in September 2015, a move that could have dramatically changed the course of the European migrant crisis that was at its peak at the time, according to a German newspaper.

The Welt am Sonntag reported Sunday that Chancellor Angela Merkel and her ministers agreed Sept. 12 to send thousands of police to the border, where they were to turn back migrants who didn’t have documents entitling them to enter Germany – “including in case of asylum request.”

The plan was halted hours before it was due to take effect on Sept. 13 after officials raised concerns about the border closure during an emergency meeting at Germany’s Interior Ministry, the paper reported .

Citing interviews with several unnamed high-ranking officials involved, Welt am Sonntag reported that ministers didn’t want to take responsibility for a decision that might have been illegal under German and European law. The possibility of unpopular images of police officers blocking women and children was reportedly also a concern, resulting in a change to the police order that effectively allowed all asylum-seekers to enter the country.

The interior ministry said in a statement to The Associated Press that it could “neither confirm nor deny” the report.

Had the plan been implemented, tens of thousands of migrants who were making their way northward to Germany in the fall of 2015 would likely have been stranded as countries along the route closed their borders to avoid taking them in.

It would also have marked a sharp turnaround for Merkel, who only days earlier had effectively opened Germany’s borders to migrants who were stuck in Hungary, citing humanitarian reasons.

More than half a million people – many of them Syrians, Iraqis and Afghans fleeing conflicts in their home countries – entered Germany in the last three months of 2015.

A EU deal with Turkey to prevent migrants from reaching Europe and tighter asylum rules have resulted in a marked drop in arrivals since then.