British Prime Minister Theresa May must raise human-rights concerns with President Recep Tayyip Erdoğan when she travels to Turkey, Amnesty International UK said on Tuesday (24 January 2017). The human-rights group issued the request after Number 10 announced that May would fly from the US to Ankara on Saturday.

"This visit is a vital opportunity for Theresa May to ask some probing questions over Turkey's human-rights crackdown following last year's bloody coup attempt," Kate Allen, Amnesty International's UK director, told IBTimes UK.

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"Human-rights abuses during the attempted coup absolutely must be investigated and their perpetrators brought to justice, but this can't be done at the expense of fundamental rights.

She added: "We've gathered disturbing evidence of widespread torture in the immediate aftermath of the would-be coup, and the rights of detainees have also been severely curtailed in a series of executive decrees.

"May should call for journalists held in pre-trial detention in Turkey to be released, for an end to torture in detention and for due process and the rule of law in Turkey to prevail."

The Conservative premier's visit would follow her summit with Donald Trump in Washington on Friday and be May's first visit to Turkey as prime minister. The leaders are expected to hold wide-ranging discussions on trade, defence and security, according to Downing Street.

Turkey is a key Nato ally and the nation's deal with the EU to combat the migrant crisis has seen what has been called a 'substantial fall' in people using the Aegean Sea to access Europe, according to the European Commission.

The UK continues to support Turkey's accession to the EU and a Number 10 spokesperson reportedly described Erdoğan as an "indispensable partner". But campaigners have raised concerns Erdoğan's crackdown on political opponents after a failed coup attempt in July 2016. Tens of thousands of people, including judges, lawyers, teachers and journalists, have been arrested and detained by Turkish authorities as part of the post-coup crackdown.

Andrew Smith, of the Campaign Against Arms Trade (CAAT), told IBTimes UK that May must stop UK arms sales to Turkey. "Turkey has moved in an increasingly authoritarian direction under President Erdoğan, particularly in the aftermath of last summer's crackdown," he said.

"There have been major attacks on press freedom and serious allegations of torture. If May is concerned for those being repressed by the Turkish authorities, then she must stop the arms sales and use her influence to call for positive and meaningful change."

CAAT has claimed that Britain has sold £355m ($442m)-worth of arms to Turkey since Erdoğan's election in August 2014.

Foreign Secretary Boris Johnson visited Turkey in September to discuss the Syrian civil war, UK-Turkish trade relations and the fight against the group calling themselves Islamic State (Isis). "I had the opportunity to build on the considerable co-operation that already exists between our two countries, and consider how we can better harness the enormous trade opportunities we have," he said.

Johnson, a Vote Leave campaigner in the run-up to the EU referendum in 2016, won a poetry prize for offensive prose about Erdoğan and a goat, held by The Spectator in May last year.

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