Updated

Europe's top human rights institution is urging Turkey's leaders to "urgently change course" and reverse violations of media freedoms and the rule of law, voicing alarm over democracy in the country.

The call comes as Turkey is set to hold a referendum in April on switching to a presidential system — a move critics fear will concentrate too many powers in the hands of President Recep Tayyip Erdogan.

The Council of Europe's Commissioner for Human Rights, Nils Muiznieks, said in a report released Wednesday that Turkey's already worrisome state of media freedoms and freedom of expression had reached "seriously alarming" levels since a state of emergency was declared following a failed coup attempt.

The commissioner also expressed concerns over the constitutional amendments that will be voted on in the referendum.