(File image) US Army Private First Class Bradley Manning

Washington - A United States Army judge on Thursday ruled that charges of aiding the enemy would be upheld in the case against US soldier Bradley Manning, suspected of leaking hundreds of thousands of classified documents to the whistleblower website WikiLeaks.

Manning's defence team earlier this week argued that all 22 charges against him should be dismissed.

But Army Colonel Denise Lind, the judge presiding over the high-profile case, also noted that the prosecution must prove that Manning understood that the enemy would have access to the data he provided to WikiLeaks.

Manning's trial is set to begin on September 21 and run through October 12, according to the Pentagon.

He could face life in prison if found guilty on all the charges. - Sapa-dpa