HELSINKI, May 17 (Reuters) - Finland's state-owned energy provider Gasum said on Tuesday it would take its dispute over rouble payments with Russia's Gazprom Export to arbitration proceedings.

Gasum said it will not accept Gazprom Export's demand to pay in roubles for its gas supplies to Finland and therefore there was an increased risk that Russian gas flows to Finland could be halted.

"In this situation, Gasum had no choice but to take the contract to arbitration. In this challenging situation, we will do our utmost to be able to supply our Finnish customers with the energy they need," Gasum CEO Mika Wiljanen said in a statement.

Gasum said it would aim to supply Finnish customers during the summer through the BalticConnector gas pipeline which links the Finnish and Baltic gas grids across the Gulf of Finland.

Constraints on the pipe's transmission capacity, however, could make this challenging, it added.

In the longer term, Finland plans to jointly lease a floating terminal with Estonia to import liquefied natural gas (LNG).

Finland imports most of its gas from neighbouring Russia but gas accounts for only about 5% of its annual energy consumption.

Losing that supply, however, could affect Neste, Metsa and other companies in the forestry, chemical and food industries.

Last Friday, the European Commission published updated guidance on how EU companies can pay for Russian gas without breaching the bloc's sanctions.

(Reporting by Anne Kauranen; editing by Louise Heavens and Jason Neely)