German conservative leader Friedrich Merz is set to take his hard-line immigration push to the next level despite a growing backlash over his move this week to force a resolution through parliament with backing from the far right.

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.

A 99-year-old Holocaust survivor said on Thursday he would return his federal order of merit award to the German state in protest over a parliamentary vote in which support from the far-right was used for the first time to secure a majority.

Friedrich Merz’s hard-line shift on migration is a calculated gambit by the German conservative leader to neutralize the far right and deliver a breakthrough with wavering voters, according to people familiar with his thinking.

Germany's conservative opposition leader was set Friday to again seek far-right support in parliament on the flashpoint issue of immigration, after his first effort sparked widespread condemnation and street protests.

Protesters in Germany on Thursday rallied against the conservative CDU party to decry its cooperation with the far-right AfD in pushing through parliament a motion to demand a crackdown on immigration.

Germany's ex-chancellor Angela Merkel weighed in Thursday on a controversy flaring ahead of February elections, slamming her party successor for relying on far-right support on the flashpoint issue of immigration.