Angela Merkel, has been criticised by members of her cabinet after acceding to a request from Ankara to prosecute a comedian who read out an offensive poem about the Turkish president, Recep Tayyip Erdoğan.

The German chancellor insisted her government's decision did not amount to a verdict on whether Jan Böhmermann was guilty or not, but should be understood as a reaffirmation of the judiciary's independence.

"In a constitutional democracy, weighing up personal rights against freedom of the press and freedom of expression is not a matter for governments, but for public prosecutors and courts," Merkel said in a press conference on Friday.

The chancellor expressed "grave concerns" about the prosecution of individual journalists in Turkey, as well as growing limitations to the right to protest, but emphasised Germany's close diplomatic ties with the country.