(Corrects JULY 11 story to clarify Solveig Gas, Infragas owned by different pension funds)
* Norway to cut gas transportation tariffs by 90 pct
* Three companies say they intend to claim for losses
OSLO, July 11 (Reuters) - Several partners in Norway's offshore gas pipeline system Gassled intend to sue the Norwegian state over losses due to cuts in gas transportation tariffs, they said on Thursday.
Companies, representing several international investment funds, such as the Abu Dhabi Investment Authority, Canadian pension funds and German insurer Allianz, have spent $5.1 billion in recent years acquiring stakes in Norwegian pipelines, then considered a safe and steady investment bet.
The government said at the end of June it would stick to an earlier announced plan to lower the tariffs by 90 percent for new gas contracts, a move it said was intended to encourage higher production in mature fields and exploration in the frontier areas of the Arctic.
Though the government decided that lower tariffs will apply from 2016 instead of this year as previously planned, investors insist the decision to cut them lacks legal basis and should be declared invalid. The government says it acted legally.
Njord Gas Infrastructure AS, Solveig Gas AS and Silex Gas AS said they all notified Norway's oil and energy ministry on Thursday about their intention to bring legal action against the Nordic state to claim compensation for the losses.
"Notice contemplates that the company would claim compensatory damages for the loss the company suffers as a result of the decision," Njord Gas, which holds 8 percent of Gassled, said in a statement to the Oslo Stock Exchange.
Trygve Pedersen, head of Solveig Gas Norway, owned by the Canada Pension Plan Investment Board, the Abu Dhabi Investment Authority and Allianz, said the notification was "the initial step in the legal proceedings."
"We are basically notifying that their (ministry's) decision lacks legal foundation, and that we will claim financial losses," he added.
Kurt Georgsen, Chief Executive Officer of Silex Gas, a subsidiary of Allianz Capital Partners, said litigation could be avoided if the ministry changes its position.
The three companies together hold almost 39 percent of Gassled venture. Norway's state-owned Petoro is the major stakeholder with 45.8 percent.
Norway's oil and energy ministry confirmed receiving letters from the three companies.
"We are taking them into the consideration," a spokeswoman said, declining to comment further.
Infragas Norge AS, wholly owned by another Canadian pension fund, the Public Sector Pension Investment Board, which has also protested against the government's proposal, said it was still assessing the situation.
Norway exports gas via an 8,000-kilometre-long network to receiving terminals in Britain, France, Belgium and Germany.
Last year, Norway overtook Russia to become the European Union's biggest gas supplier, delivering 106 billion cubic metres of gas. (Reporting by Nerijus Adomaitis; Editing by David Evans)