An ally of Chancellor Angela Merkel has warned that her Christian Democrat CDU could face a challenge if a new party were to emerge on the right.

In response to fears that the party could face a challenge on its right flank, Wolfgang Boehmer - who is CDU premier of the state of Saxony Anhalt - warned against complacency.

"The danger that a populist right-wing party might emerge always exists," said Boehmer in the German daily newspaper Hamburger Abendblatt on Saturday. "even if at the moment we cannot recognize who could lead it. We must always be on our guard and undertake everything to avoid the founding of another party to the right of our own."

When asked if the party was adhering sufficiently to its conservative roots, Boehmer said that constant vigilance was necessary.

"We have to repeatedly pose the question of whether conservatives identify with the CDU," he said.

As a mainstream party, said the premier, it was not possible for the CDU to move too far to the right. Instead, he said, the problems that were important to ordinary people should be clearly addressed. "That is the best immunization against far right extremist attitudes," said Boehmer.