An Iraqi court has dismissed a $4.5 billion lawsuit against Zain over its 2007 acquisition of an Iraqi telecom operator, the Kuwaiti group said on Monday, although the claimants can still appeal for a final time.

Zain bought Iraqna for $1.2 billion from Orascom Telecom in December 2007 after the Egyptian company dropped out of the running for a long-term mobile licence in Iraq.

The Kuwaiti firm then merged its Iraqi unit, Atheer, with Iraqna and renamed the entity Zain Iraq, which today is the country's biggest operator by subscribers.

The claimant's lawsuit argued Zain's takeover had stopped the firm buying Iraqna, causing it a $4.5 billion loss.

An Iraqi court dismissed the case in July, but the unnamed claimants (indentified by industry sources as shareholders in No.3 mobile operator Korek) successfully appealed and a court ruled in their favour. Zain then mounted its own appeal to a higher court, which subsequently instructed the lower court to reconsider its verdict.

The lower court then decided it had erred in its original verdict, reversing its decision and finding in favour of Zain, a statement to Kuwait's bourse said.

The claimants, who have 30 days to launch a final appeal or the case will be closed, had also jointly sued Zain and Iraq's telecom regulator, the Communications and Media Commission (CMC), for a further $1 billion.

Korek and CMC could not be reached immediately for comment.