Turkey human rights abuses overshadow PM's trade deal talks with President Erdogan

The PM's trip will be used to prepare the ground for a formal trade agreement after Brexit

The Turkish President Recep Tayyip Erdogan has been criticised for his crackdown on opponents since the failed coup last year (Reuters)

Theresa May will unveil fledgling trade discussions with Turkey as she arrives in the country for her first visit.

But the announcement comes as questions still hang over the Turkish President's severe response to the coup which has resulted in a crackdown on his opponents.

Ms May's trip to Turkey will be used to promote a new "joint working group" to prepare the ground for a formal trade agreement after Brexit.

A Downing Street official said the group would involve "work that goes on between officials to look at liberalising trade, reduce tariffs and pave the way for future trade cooperation".

But her visit comes after Mr Erdogan declared a state of emergency following last summer's coup attempt, which was followed by a wave of arrests, the closure of numerous media outlets and the removal of thousands of public officials – including judges, teachers and university academics – from their jobs.

According to Amnesty International, the human rights situation in the country has "deteriorated markedly" since the coup, including cases of excessive use of force by police and ill treatment in detention.

The group has said Ms May's visit is a "vital opportunity" to raise concerns with the country's increasingly powerful leader, whom Number 10 characterised as an "important ally".

Asked if she would raise human rights, a spokeswoman said: "The Prime Minister's approach is quite clear – she thinks it's important, and in the UK's national interest – to engage with Turkey on a range of issues – from defence and security cooperation to capitalising on trade opportunities."

But she went on: "We have already expressed our strong support for Turkey’s democracy and institutions following the coup – but we have also been clear that we urge Turkey to ensure that their response is proportionate, justified and in line with international human rights obligations."

Ms May will also use the visit to Ankara to deepen security cooperation, particularly in relation to counter-terrorism and aviation. The joint working group on trade is the 13th that the UK now has with countries as it looks to cement its future trade relations with the world after Brexit.