Theresa May, left, meets Turkish President Recep Tayyip Erdoğan in Ankara on January 28 | Andrew Parsons/Pool via Getty Images Theresa May revives arms deal with Erdoğan’s Turkey British prime minister proclaims ‘strategic partnership’ with regime in Ankara shunned by much of EU.

ANKARA — British Prime Minister Theresa May, swinging through the Turkish capital on her way back from Washington, sealed a potentially transformative arms deal with Ankara on Saturday that will see British engineers help design and build 250 fighter jets for Turkey.

The agreement, which was put on ice after the attempted July coup against President Recep Tayyip Erdoğan and his subsequent crackdown against the opposition and media, paves the way for a new Anglo-Turkish defense partnership that the U.K. government believes will effectively make Britain Ankara’s “industrial partner of choice.”

The initial £100 million deal is seen as a “gateway” agreement potentially worth “billions” to the U.K. economy, a Downing Street spokeswoman said. The wider program could see Britain provide engines, weapons, radars and sensors to the Turkish military.

"It is important Turkey sustains democracy by maintaining rule of law and upholding human rights obligations" — Theresa May

May’s decision to embrace Erdogan — becoming the first Western leader to visit Ankara since the failed coup on July 15 — comes despite mounting concerns over human rights abuses in the country and contrasts with the chilly relations between Ankara and the European Union over recent years. While the EU has relied on Turkey to help stem the tide of hundreds of refugees into Europe, it has also criticized the authoritarian turn by Ankara and put accession talks on ice.

'Strategic partnership'

After their private one-on-one talks at the presidential palace in Ankara, the leaders agreed a new “strategic security partnership” between the two countries, with officials set to meet every six months.

Asked directly whether it was appropriate for the U.K. to be selling arms to the Erdoğan government, the Downing Street spokeswoman insisted human rights concerns were a “separate” issue and that the deal was “justified and important.”

Speaking in front of the cameras while Erdoğan looked on, May did raise the issue. "I'm proud that the U.K. stood with you on 15 July last year in defence of democracy and now it is important that Turkey sustains that democracy by maintaining the rule of law and upholding its international human rights obligations as the government has undertaken to do," she told the Turkish president.

When May arrived for talks with the Turkish leader, Erdoğan pointed to a huge TV in the corner showing scenes from the U.K. prime minister’s visit to the White House the day before. May laughed in surprise. "It was well covered in Turkey," an aide to the president explained. May smiled. "Well covered," she repeated, and smiled again.

After her meeting with Erdogan, May said the arms agreement signaled “the start of a new and deeper trading relationship with Turkey” following Britain’s decision to leave the European Union.

It comes after Downing Street announced Friday that Britain and Turkey will set up a working group to prepare the ground for a bilateral trade deal after Brexit.