Lawyers for WikiLeaks suspect Bradley Manning called for the charges against the US Army private to be reduced as a hearing to decide if he should face a court-martial ended Thursday.

The defense appeal came during closing arguments at the end of a seven-day pre-trial hearing for the low-ranking soldier blamed for one of the most serious intelligence breaches in US history.

"The government overcharged in this case," said Manning's civilian defense attorney David Coombs.

Manning, 24, faces life in prison if convicted of aiding the enemy, the most serious of the 22 charges he is facing over the leak of hundreds of thousands of military documents and diplomatic cables to the anti-secrecy website WikiLeaks.

Coombs said all of the charges should be dropped except for three that carry the possibility of 30 years in prison.

US Army prosecutors urged the presiding officer, Lieutenant Colonel Paul Almanza, to recommend a court-martial on all the charges.

Almanza is not expected to make a decision for several weeks.