A meeting sponsored by the United Nations in Tunis this week will seek to resolve a challenge to American authority over the Internet Corporation for Assigned Names and Numbers (Icann).

The World Summit on the Information Society will consider calls for an end to Icann's unilateral control, and will suggest the alternative view that the internet cannot adapt well to centralised or governmental control which could end up fragmenting the network itself.

"There is going to be a nasty fight," said one international official speaking to the Financial Times. "I don't see any room for agreement."

At last month's preparatory meeting in Geneva for the World Summit, the European Union insisted on a new "co-operation model" for the overseeing of internet addressing systems, and called for a forum that would decide public policy.

The US defended its position saying that the proposed changes go against the "historic role" that the US has played in controlling the top level of the internet.

Meanwhile a journalist attending the summit was attacked near his hotel on Friday. Christophe Boltanski, who writes for Liberation, was beaten, stabbed and robbed by four unidentified assailants near his hotel in the Tunisian capital.