LONDON, Jan 4: A deal that would clear the way for Iran to start up its Russian-built Bushehr nuclear power plant has been delayed over Moscow's fee for taking back Russian-made spent fuel, Russia's nuclear chief said on Tuesday.

"We have told them they have to pay for spent fuel, just like fresh fuel," Alexander Rumyantsev, head of Russia's Atomic Energy Agency, said after an informal meeting with US Energy Secretary Spencer Abraham.

Rumyantsev on Tuesday rejected earlier reports that said the Iran agreement could be signed as early as January, adding Russia and Iran had until mid-year to finalise the agreement.

With Iran accused by the United States of seeking nuclear weapons, Russia and Iran have promised the United States they will sign a deal to remove spent fuel from Iran before the Bushehr plant is switched on.

Some diplomats say Russia is stalling on the spent-fuel re-import deal with Iran to keep Washington friendly while hedging its bets with the Islamic Republic. The agreement must be signed in time to start shipping fresh fuel to Iran for the scheduled launch of Bushehr in early 2006, Rumyantsev said.

Some legal hurdles, included possible successors to the two countries' agents, Russian nuclear fuel producer TVEL and the Iranian Atomic Energy Agency, and the pricing of Russia's re-import services, had been dealt with, he said. -Reuters