Vienna

It's the first time a European city has topped the rankings of the Economist Intelligence Unit annual global survey.

The worldwide league table ranks 140 cities on a range of factors, including political and social stability, crime, education and access to healthcare.

In the survey, Manchester saw the biggest improvement of any European city, rising by 16 places to rank 35th.

Manchester's rise puts it ahead of London in the rankings by 13 places, the widest gap between the two cities since the survey began two decades ago.

The issue was raised on the sidelines of negotiations in Vienna earlier this month that led to the landmark deal on curbing Iran's nuclear program.

Abbas Araghchi told reporters in the Iranian capital on Wednesday that cases of "imprisoned citizens" were discussed with their American counterparts during the nuclear talks.

He says "humanitarian" reasons had motivated the discussion but did not elaborate.

He will meet there with U.S. Secretary of State John Kerry in an attempt to resolve disputes that have forced an extension of the negotiations past the June 30 deadline.

Lavrov is to arrive Tuesday, the day that Iranian Foreign Minister Mohammad Javad Zarif returns to Vienna.

As Zarif flew home Sunday for consultations on how to proceed at the talks, a U.S. official confirmed that negotiators will miss a June 30 target date for a deal, aimed at limiting Tehran's nuclear program in exchange for sanctions relief.

The State Department said in a one-sentence statement on Wednesday that Kerry would leave for the Austrian capital on Friday. It will be his first overseas trip since breaking his leg in a bicycle accident earlier this month after a meeting with Iranian Foreign Minister Mohammad Javad Zarif in Geneva.

Diplomats from the United States, the other four permanent members of the U.N. Security Council and Germany have been in intense discussions with Iranian officials in Vienna as the end-of-month deadline for a deal looms.