UPDATE 2-Areva-Siemens says wins partial ruling on Finland delay

(Adds TVO comment)

PARIS/HELSINKI, July 5 (Reuters) - French nuclear-reactor maker Areva said on Thursday its consortium with Siemens had won a partial arbitration ruling against Finnish utility TVO in a dispute over delays and cost overruns at the Olkiluoto 3 reactor.

TVO has been asked to pay 125 million euros ($154.76 million) to Areva-Siemens in unpaid construction fees and accrued interest as a result of the ruling by the International Chamber of Commerce's arbitration court, Areva said.

That still leaves the bulk of the 1.94 billion-euro dispute to be decided, however, an Areva spokeswoman said. "(The dispute) covers delays and other problems encountered by the project as part of the contract's execution," she said.

TVO's spokesman Lauri Inna the ruling was about earlier payments that had been withheld and will now be delivered to Areva-Siemens.

"This ruling is not about the actual dispute about the delay of the plant delivery. That process still continues," he said.

The 1,600 megawatt Olkiluoto 3 plant, Finland's fifth nuclear reactor, was originally scheduled to start operations in 2009 but delays and soaring costs meant TVO has had to repeatedly push back its start date.

Areva-Siemens brought the dispute to arbitration in 2008.

TVO's biggest owners include Finnish utility Fortum and Pohjolan Voima, a consortium of Finnish forestry and energy firms. ($1 = 0.8077 euros) (Reporting by Lionel Laurent; Additional reporting by Terhi Kinnunen; Editing by Christian Plumb and Tim Dobbyn)