Former German Chancellor Angela Merkel has issued rare public criticism of her successor as the country’s center-right leader, the front-runner in Germany’s election next month, for putting to parliament proposals for tough new migration rules that only passed with the help of a far-right party.

The German Catholic bishops’ conference on Wednesday distanced itself from a controversial statement against tougher migration policies issued by its Berlin office just before Parliament approved a motion on stronger border controls with support from the Alternative for Germany (AfD) party.

Germany’s parliament has narrowly approved a call by Chancellor Olaf Scholz’s main challenger to turn back many more migrants at the country’s borders, with the help of a far-right party.

Germany's opposition conservatives won parliamentary approval on Wednesday for a proposal to drastically restrict migration with the help of votes from the Alternative for Germany (AfD), breaking a taboo on cooperation with the far-right.

With less than four weeks before Germany’s federal election, Chancellor Olaf Scholz and his conservative challenger Friedrich Merz, who is leading polls, will take their contentious battle over how to crack down on illegal migration to parliament.

German election frontrunner Friedrich Merz succeeded on Wednesday in getting a motion passed in parliament that calls for a migration crackdown including the rejection of asylum seekers at the country's land borders.