Royal Dutch Shell plans to invest in Iran's energy and petrochemical projects soon, said the head of the investment department at National Petrochemical Company (NPC).

NPC and Shell recently inked a letter of intent to start discussions on renewal of petrochemical and energy-related activities in the Islamic Republic, reported Iran Daily.

"The deal does not specify any activities so not to limit its range," Hossein Alimorad was quoted as saying in the report, which cited Shana.

Based on the document, the two sides will indicate their willingness to cooperate in any field they are interested in, he added.