MOSCOW (Reuters) - Igor Sechin, the head of oil giant Rosneft <ROSN.MM>, says it is planning energy projects in Belarus, Russian media reported on Saturday, a sign the close Kremlin ally will not let a potash dispute undermine the Russian state firm's business in Belarus.

The collapse of a potash trading agreement in July triggered a diplomatic spat between Russia and its ex-Soviet ally, including Belarus's arrest of the head of Russian fertiliser firm Uralkali <URKA.MM>.

The arrest put a new strain on the close but sometimes tense relationship between Russia and Belarus, which relies on Moscow for energy supplies and financial help but is important to the Kremlin as a military and economic ally.

However, Sechin, who is a close confidant of Russian President Vladimir Putin, appears committed to maintaining strong business ties with Belarus, a lucrative market for Russian energy firms due to an export tax waiver.

"Of course we have plans (in Belarus) - there is talk of oil projects and of oil and gas projects," RIA Novosti news agency quoted Sechin as saying.

The potash disagreement will not impact Rosneft's Belarussian plans, Sechin added, according to RIA. "It doesn't affect us... we have stable, normal partners."

Reports that Uralkali's top shareholder Suleiman Kerimov, whom Belarus has accused of abuse of power, is selling his stake are likely to have been welcomed by Belarus, with one commentator suggesting a deal would secure the release of the firm's chief executive from prison.

Sechin's comments follow a meeting on Wednesday between him and authoritarian Belarussian President Alexander Lukashenko in Minsk and the news that Russia's oil pipeline monopoly Transneft would cut supplies less than previously planned, despite the need for repairs.

RIA reported on Saturday that Sechin said Rosneft, which accounts for around half of Russian oil flows to Belarus, was not planning on cutting its oil supplies to the country, although exports were hampered by infrastructure constraints.

State-controlled Rosneft will produce more oil in 2014 than the 206 million tonnes it forecasts it will pump this year, Sechin added.

Belarus arrested Uralkali's CEO, Vladislav Baumgertner, on August 26, charging him with abuse of office.

(Reporting by Alessandra Prentice; editing by James Jukwey)