London and Birmingham are the highest-ranking cities for quality of life in the UK, followed by Glasgow and Aberdeen, a survey suggests.

Vienna retains the top spot worldwide, with Zurich, Auckland and Munich following respectively, according to Mercer's quality of living survey.

Globally, Baghdad is ranked bottom at 221 and London comes in at 38 –although it reaches sixth place for the quality of its infrastructure, based on electricity supply, water availability, communication services and public transport.

Slagin Parakatil, senior researcher at consultancy firm Mercer, said: "London's high ranking in the infrastructure index reflects a combination of a high level of public services offered, with its extensive public transportation system including airports, the London Underground, buses and railroad services."

Singapore hits top spot for best infrastructure, followed by Frankfurt and Munich in second place, and Port-au-Prince in Haiti coming in last.

Europe has 15 cities among the world's top 25 cities for quality of living, with most of the top 10 dominated by German and Swiss cities, with three cities each in the top 10.

The lowest-ranking Western European cities are Athens at 83 and Belfast at 64, while the lowest in Eastern Europe is Tbilisi in Georgia at 213.