Reuters reporting

Iran has cancelled a London conference where it was due to introduce new oil and gas contracts to investors, Seda reported today citing a senior Iranian official who blamed a delay in getting visas.

The conference, set for Feb 22-24, has been postponed 5 times amid uncertainty over international sanctions against Iran which were lifted earlier in Jan.

Foreign companies will now be invited in May to bid for the new Iran Petroleum Contracts (IPCs), Ali Kardor, deputy head of the National Iranian Oil Co. (NIOC), told Seda.

Iran is changing the terms of its oil development contracts to lure back international companies in order too bolster its economy,

Some 135 firms, including BP, France's Total, Italy's Eni, and Spain's Repsol attended a conference in Tehran in November to hear about the IPC.

Hardline rivals of pragmatist President Hassan Rouhani have criticised the new contracts, however.

Reuters has more here.

Not going to have any major impact on oil price but all part of the back story.