The usefulness of a British passport waned in 2019, according to a ranking compiled by the residence and citizenship planning specialists Henley & Partners.

In the latest Henley Passport Index, which ranks 199 of the world's passports by the ease with which they offer access to other nations and territories, the United Kingdom slipped farther from the first place it held in 2015, down to joint-eighth.

Paddy Blewer, group public relations director at Henley& Partners, told Euronews that is "unknown whether the British passport will fall post-Brexit with regards to value".

Asian nations were the big winners this year; with Japan's passport named the best for the third year in a row, Singapore's remaining in second place, and South Korea's moving up to share third with Germany.

Henley & Partners compiled its list by analyzing data produced by the International Air Transport Association, and by conducting research of its own.

Passports score well by offering their citizens visa-free access to destinations, or visas-on-arrival. In the case of Japan, the nation's passport opens the door to 191 countries and territories.

The Independent newspaper quoted Christian H Kaelin, chairman of Henley& Partners, as saying: "Asian countries' dominance of the top spots is a clear argument for the benefits of open-door policies and the introduction of mutually beneficial trade agreements."

Kaelin said people increasingly want easy access to other economies.

"Over the past few years, we have seen the world adapt to mobility as a permanent condition of global life," he said. "The latest rankings show that the countries that embrace this reality are thriving, with their citizens enjoying ever-increasing passport power and the array of benefits that come with it."

European nations also fared well, with Finland, Italy, Denmark, Luxembourg, Spain, France, Sweden, Austria, and Ireland all near the top.

The United Arab Emirates has arguably been the index's biggest success story of the past decade, climbing 47 places to 18th and now offering easy access to 171 destinations.

People living in the Hong Kong Special Administrative Region of China hold passports that are ranked joint-20th in the listing, while those living in the Macao Special Administrative Region have passports ranked 34th. The passport held by citizens of the Chinese mainland was ranked in joint-72nd place. It offers easy access to 71 destinations.

Afghanistan was at the bottom, with a passport that qualifies for easy access to 26 destinations.