BAGHDAD – A report that the United States spied on Iraqi officials shows a lack of trust and casts a shadow over relations with U.S. intelligence agencies, the Iraqi government said on Friday.

The Washington Post said on Friday that a book by U.S. journalist Bob Woodward reported that the United States spied on Iraqi Prime Minister Nuri al-Maliki and other Iraqi leaders.

'If it is true...it reflects that there is no trust,' government spokesman Ali al-Dabbagh said in a statement.

Iraq will ask the United States for an explanation, he said.

The U.S. embassy in Baghdad said it had no immediate comment on the report, detailed in Woodward's fourth book on U.S. President George W. Bush, entitled 'The War Within: A Secret White House History 2006-2008.'

'If it is true it casts a shadow on the future relations with such institutions,' Dabbagh said, referring to the Central Intelligence Agency and other U.S. agencies.

Woodward writes that the surveillance of the Iraqi prime minister caused concern among several senior U.S. officials, who questioned whether it was worth the risk given Bush's efforts to earn Maliki's trust, The Washington Post reported.

(Writing by Mohammed Abbas: Editing by Angus MacSwan)