Tests have been carried out to see whether adding foreign characters to web domain names would disrupt the speed of the internet.

The international character sets were tested in October last year, and results published this week show that the additional characters did not slow down web access.

"All answers were consistent with expected behaviour and no unexpected delays were discovered," Lars-Johan Liman, a senior systems specialist at Swedish firm Autonomica AB, said in a report on the experiment. 

The Internet Corporation for Assigned Names and Numbers, which carried out the tests, hopes to add character sets such as Chinese and Arabic by 2008. 

However, China is already working on its own system to add its language to web domain names. The Chinese government released a software plug-in a year ago that allowed Mandarin letters to be used in browsers.

Currently sites must use just 37 characters to create their web address, including the English alphabet, the numbers zero to nine and a dash.