Eircom shareholder Telia and Sonera, the two top telecoms carriers in Sweden and Finland, are teaming up with new partners to form the first pan-Russian mobile operator in a move to exploit a largely untapped market.

Sonera said yesterday that the new joint venture, which has yet to be named, would have around 400,000 mobile subscribers after linking up with Russian investment group AO Telecominvest, Central Telegraph Mobile and three other Russian partners.