Iran's central bank has received a total of $1 billion of previously frozen oil revenue from Japan under the terms of an extended nuclear agreement with six world powers, state news agency IRNA reported on Thursday.

Iran and the United States, China, France, Germany, Britain and Russia agreed in July to extend a six-month interim accord until November 24 after they failed to meet a July 20 deadline for reaching a long-term deal to end their nuclear dispute.

In return for continuing action to curb its nuclear programme, Iran would receive $2.8 billion during the four-month extension of its funds held in foreign banks, in addition to $4.2 billion paid during the January-July period.

US officials say more than $100 billion of Iran's funds are held abroad and are difficult to access because of tightening sanctions on the major oil producer in recent years.

The UN nuclear agency confirmed on August 20 that Iran was moving to meet the requirements of the extended agreement, paving the way for some of the money to be released.

Citing the Iranian central bank's public relations office, IRNA said Japan's central bank deposited the funds in two instalments at the Iranian central bank's account in Oman.

Japan, China, India and South Korea are the biggest buyers of Iranian crude. Japan, along with South Korea and India, cleared some of its oil dues earlier under the payment schedule agreed with the six powers in the interim agreement.

The nuclear negotiations are due to resume later this month in New York. The six powers want Iran to significantly scale back its uranium enrichment programme to make sure it cannot produce nuclear bombs. Iran says the programme is peaceful.

Under the interim deal that was reached in Geneva in November and took effect in January, Iran agreed to halt its most sensitive nuclear activity in exchange for some sanctions easing. It was designed to buy time for talks on a long-term settlement. - Reuters