Iran has asked to import a million tonnes of wheat from Pakistan in a barter deal, a senior official in Islamabad said on Friday, as Tehran faces disruption to its food imports because of U.S. and European Union sanctions.

Iran would export iron ore and fertiliser to Pakistan in exchange for wheat, said Syed Naveed Qamar, Pakistan's minister for water and power, according to the state news agency.

Qamar added that Iran would also import 200,000 tonnes of Pakistani rice.

Some things need to be worked out before we can say for sure if and when this will happen, a senior official at the Commerce Ministry told Reuters on Friday, requesting anonymity because he is not authorised to speak to the media.

There are payment issues because of sanctions and that makes such trades more difficult than usual.

Iranian President Mahmoud Ahmadinejad visited Pakistan last week for a trilateral summit on regional security with his Pakistani and Afghan counterparts.

New financial sanctions imposed on Iran since the beginning of this year to punish it for its suspected nuclear weapons programme have greatly reduced its ability to pay for key imports, especially food.

The Government Trading Corporation of Iran (GTC) bought around 800,000 tonnes of wheat this week, trade sources said on Thursday, breaking with the previous practice of wheat purchases through the private sector.

The purchase included 500,000 tonnes from Russia and 300,000 tonnes from Australia.

The latest amounts are in addition to around 1.1 million tonnes of wheat Iran bought in the previous two weeks as traders said dry weather had stoked expectations of a poor crop and made stockpile building urgent.

Tehran has dramatically widened its reach on international grain markets in February, using currencies other than dollars and euros as alternative trade finance, with dealers also reporting talk of barter deals involving oil and gold.

Traders have said that Tehran has paid premiums well over international prices for its latest purchases, as banks in some countries began assisting Iran in financing them.

(Editing by Chris Allbritton; Editing by Nick Macfie)