In an uncharacteristic move for the long-time leader, German Chancellor Angela Merkel lashed out at a center-left candidate hoping to succeed her as the country nears elections.

Merkel added her voice to what has become a common line of argument against Social Democratic Party (SPD) candidate Olaf Scholz, who is also her current finance minister: that he is not ruling out a possible coalition with the hard-left Die Linke (The Left) party after the elections. Die Linke is polling at around 6% or 7%, and they could help form a majority as part of a left-wing coalition.

Merkel's center-right Christian Democratic Union (CDU) has rejected the idea of a coalition with Die Linke on the grounds that the party has incompatible foreign policy aims. Die Linke sees the NATO military alliance – of which Germany is a member – as a relic of the Cold War and describes it as a "war alliance."

The CDU's candidate for chancellor, Armin Laschet, emphasized in Sunday's televised debate that he would not work with Die Linke: "I. Won't. Do. It. Full stop," he said.

On Tuesday Merkel also weighed in, saying: "With me as chancellor there would never be a coalition in which Die Linke plays a part. And it's not clear whether Olaf Scholz is able to say the same thing ... This is a huge difference between me and him (Scholz) when it comes to Germany's future."

The unflappable Scholtz's solid campaign for SDP has seen his poll numbers rise above Laschet's in the past week, putting huge pressure on the center-right as they fear losing the chancellorship after Merkel's decade and a half in power.