Iran's central bank has said defaced banknotes are to be made invalid¹, after the appearance of opposition² slogans on money, local media report.

伊朗地方媒体报道，在发现钱币上出现反对派标语之后，中央银行宣布这些被损毁的钱币无效。

Many transactions are carried out in cash in Iran

They quote bank official Ebrahim Darvishi as saying that people possessing defaced被损毁的 banknotes should exchange them by 8 January.

It was difficult to distinguish genuine defaced notes from fakes, he added.

Messages in support of the opposition have been appearing on banknotes钞票，纸币 since June's disputed presidential election.

Hardline President Mahmoud Ahmadinejad was re-elected in the poll - a move that triggered mass street protests by the opposition who claimed the election was rigged作弊.

'Death to dictator'

"Banknotes on which there are writings or are stamped or have any additional signs will be invalid无效的," Iran's Jam-e Jam newspaper quoted Mr Darvishi as saying on Thursday.

The bank official also called on the public and shop owners not accept such notes from 8 January.

Since June's election, slogans such as "Death to the dictator独裁者" have appeared on many Iranian banknotes.

Opposition supporters have also sprayed喷射，散布 anti-government graffiti涂鸦 on walls in the capital Tehran and other cities.

Many transactions处理，会报 are carried out in cash in Iran, which is under international banking³ sanctions and where major credit cards cannot be used.