Singapore has fallen two places over the past 12 months to be the 14th most expensive city in the world for expatriates and it is now the seventh priciest in Asia, according to a new survey.

While Singapore has been overtaken by the Japanese cities Yokohama at 10th, Osaka at 12th and Nagoya at 13th, living costs have remained largely steady and it remains a costly location due to the strong Singapore dollar.

Hong Kong dropped out of the top five to sixth place in the survey compiled by ECA International.

Mr Lee Quane, its director for Asia, noted that there was only a "small drop in the global rankings amid the uncertainty" despite Hong Kong's political and social unrest last year and the "impact of Covid-19, which has led to the reluctance of people moving to the city".

The world's most costly city is Ashgabat in Turkmenistan, which also topped last year's league table compiled by ECA International.

The biannual survey assesses living costs in cities for non-local employees based on a basket of goods and services such as groceries, clothing and leisure activities.

Take a cup of coffee in a cafe: It is about US$4.44 (S$6.16) here compared with US$5.01 in Hong Kong and US$2.87 in Hanoi.

House rents, cars and school fees are not included in the calculations as they are usually paid for by employers and so are unrelated to an expat's spending power.

China's two powerhouses both dropped nine places in the new rankings with Shanghai at 19th and Beijing at 24.

Mr Quane said: "Chinese cities have all fallen... due to signs of a weakening economy and poorly performing currency. One of the key contributing factors was undoubtedly the outbreak of Covid-19. However, it is important to note that the renminbi was performing poorly before this period too, with the outbreak of the coronavirus exacerbating the relative weakness of the Chinese currency against other major currencies."

Similarly, the cost of living in South Korea has fallen due to the pandemic, with Seoul dropping from 8th place to 17th, while Busan slipped out of the top 20 entirely.

Mr Quane noted: "A quick lockdown, coupled with the high rates of infection that Korean cities saw towards the end of February, meant that confidence in the South Korean won had faltered. This in turns makes the cost of living cheaper for expatriates."

On the other hand, Thai and Vietnamese cities have once again moved up the rankings, with Bangkok rising 64 places in five years and Hanoi up 25 over the same period.

Mr Quane attributed Thailand's steady rise to economic growth and the attraction of foreign investment which helped to boost the baht.