Image caption Singapore has topped the Doing Business report's rankings for the past five years

Singapore remains the best country in which to run a business, according to an annual report by the World Bank.

The Asian nation has come top of the World Bank's Doing Business 2011 study, which rates 183 countries on the ease in which they allow firms to operate.

Judging nations on criteria such as how easy it is to start a business or get credit, the UK came in fourth place, while Chad was bottom.

Kazakhstan showed the most improvement over the past year.

Georgia has seen the biggest improvement over the past five years.

Published since 2004, the annual Doing Business report studies nine main criteria in total.

The other seven factors evaluated are - paying taxes, trading across borders, registering property, dealing with construction permits, closing a business, enforcing contracts and protecting investors.

It does not study wider conditions including a country's infrastructure, workforce skills, or security.

Hong Kong came in second place, with New Zealand third, and the US behind the UK in fifth place. All of the top five remained in the same position as a year earlier.

Out of the 183 countries surveyed, the World Bank said 117 implemented new business-friendly regulation between June 2009 and May 2010 - the 12 months covered for the 2011 report.

The World Bank said governments were reacting to global economic circumstances.

"Against the backdrop of the global financial and economic crisis, policy makers around the world took steps in the past year to make it easier for local firms to start up and operate," said the report.

It added: "While some economies have been hit harder than others, how easy or difficult it is to start and run a business - and how efficient courts and insolvency proceedings are - can influence how firms cope with crises and how quickly they can seize new opportunities."

On a regional basis, the latest Doing Business report found that countries in Eastern Europe and Central Asia did most to make running a business easier in the 12 months covered, with 84% of countries carrying out at least one pro-business reform.

Kazakhstan, which recorded the most improvements worldwide, carried out several measures including amending its company law, streamlining business start-up procedures, and making it simpler to get construction permits.

East Asia and the Pacific was the next best performing region, with three quarters of all countries introducing at least one reform to make life easier for firms.

Latin America and the Caribbean saw the fewest improvements, with only 47% of countries introducing one or more pro-business measures.

Singapore's 'efficiency'

Report co-author Dahlia Khalifa told the BBC that Singapore continued to lead the way for a number of reasons.

Image caption The UK remains in fourth place in the global list

"Singapore has now been top of our survey for the past five years," she said.

"It is simply the most efficient place from which to import and export. For example, you only need four documents to export and import goods, which remains global best practice.

"Singapore is also the leader in protecting investors and minority shareholders."

China, now the world's second-largest economy, trailed Singapore in 79th place.

UK praise

Regarding the UK, Ms Khalifa said the report praised the ease in which firms could get credit, and that it had some of the strongest legal rights for entrepreneurs.

The report also highlighted the UK's efficient system of credit information, and the speed in which commercial disputes were handled in the courts.

In Africa, the report said the best performing country was Mauritius, which it said was the world's 20th best place in which to run a company.

Image caption Rwanda was the second most improved country in the world in the past year

This beat a number of nation's in Western Europe including Germany (22nd in the global ranking), Belgium (25th), France (26th), Switzerland (27th), and Netherlands (30th).

South Africa is the next highest placed African nation (34th), followed by Botswana (52nd).

Rwanda, which came in 58th on the overall list, up from 70th last year, was the second most improved country in both the past 12 months and five years.

Chad was the worst performing country for the second year in succession.

'Loud' message

In Latin America, Mexico (35th) is now the best place to run a business, followed by Peru (36th). They overtake Colombia, which fell one place to 39th.

Venezuela, run by left-wing President Hugo Chavez remains the worst place in which to do business in the region, and is in 172nd place on the global list.

In the Middle East, Saudi Arabia is the best performing (11th globally), followed by Bahrain (28th), and Israel (29th).

"We are very pleased to see that more and more countries are making it easy for companies to do business," added Ms Khalifa .

"The message is loud and clear - countries realise they have to be serious about getting small and medium-sized firms up on their feet and creating jobs."