Erdogan held talks with May at 10 Downing St. on the final day of a three-day trip to the U.K. that included an audience with Queen Elizabeth II at Buckingham Palace and drew protests. Kurdish activists and human rights groups rallied outside May's office before the meeting, condemning Erdogan's increasingly autocratic rule.
His government arrested more than 50,000 people following a July 2016 coup attempt, and some 38,000 people still are behind bars for alleged links to the failed overthrow. More than 110,000 people have been purged from government jobs through emergency decrees.
Among the protesters in London on Tuesday were journalism groups calling for the release of detained media workers. At a news conference with May, Erdogan insisted Turkey had jailed journalists with alleged links to crime and terror activities.
"Just because they are journalists, just because they have a (press) card, doesn't mean everything is allowed," he said. "A terrorist cannot be a journalist."
May acknowledged that Turkey faced "extraordinary pressures from the failed coup, instability across the border from Syria and from Kurdish terrorism." But she said it was important that Britain's fellow NATO member "does not lose sight of the values it is seeking to defend."
"That is why today I have underlined to President Erdogan that we want to see democratic values and international human rights obligations upheld," the prime minister said.
Turkey is a key partner for Britain in the fight against Islamic State group militants. The U.K. is also seeking to bolster trade with Turkey after it leaves the European Union in 2019.
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