On Friday, Icann, the US-based organisation responsible for overseeing internet domain names, announced that it had exchanged letters with Nominet, the company that manages the UK's top-level domain.

Nominet is the fourth largest internet registry, responsible for five million domain names in the ccTLD (country-code top-level domain) ".uk" according to the company's website.

Nominet executives have been vocal critics of Icann (the Internet Corporation for Assigned Names and Numbers), calling for more transparency given its powerful influence in the functioning of the internet. In 2001, Nominet withdrew from an Icann sub-body, the Domain Names Supporting Organisation, over concerns about Icann's operating policies.

That dispute appears to have diminished, partly as a result of assurances from Icann that it would listen to the ccNSO (country-code Names Supporting Organisation), another policy development body within Icann. The ccNSO develops policy related to ccTLDs. Nominet will now participate in that group. The German ccTLD registry, Denic, which manages the ".de" suffix, joined in May.

"There weren't really policy changes," said Andrew Robertson, Icann spokesman in Europe. "There were clarifications that Icann board wouldn't unilaterally act on recommendations that come up from the ccNSO organisation, and the Icann board wouldn't make unilateral decisions contradicting it."

Icann said in a statement that it has been working with ccTLDs since 2000, but the relationships are "complex" due to different economic, language, cultural and legal environments. Nominet is the seventh registry to formalise a relationship with Icann in the past two months.

In February, Icann introduced a program called the Accountability Framework for formalising relationships with ccTLDs, including guidance on dispute resolution and terminations.

Icann, a nonprofit organisation, oversees the domain name registration system and root name servers, the system that translates domain names into the numeric addresses needed to serve a web page. Icann controls the Iana (Internet Assigned Numbers Authority), which manages the master domain name lists held by the 13 so-called "root" machines.

Icann's close relationship with the US Department of Commerce has driven calls for a more international governance model. The two entities have a memorandum of understanding that is set to expire later this year.

Officials from Nominet could not immediately be reached for comment.