A military judge will rule Thursday whether to drop some charges against Bradley Manning, the US soldier who has admitting giving a massive cache of secret documents to WikiLeaks.

As the espionage trial enters its final stage, Manning's defense lawyer, David Coombs, renewed his request Monday for the judge to toss out several counts -- including the most serious charge that the soldier "aided the enemy" -- on grounds the prosecution has failed to provide incriminating evidence.

Apart from the aiding the enemy count, the defense has asked Judge Denise Lind to toss out charges that Manning committed computer fraud by allegedly exceeding his authorized access and that he allegedly stole government property in his document dump.

The former intelligence analyst in Iraq already has pleaded guilty to ten lesser offenses, acknowledging that he passed hundreds of thousands of military intelligence reports and State Department diplomatic cables to WikiLeaks in the biggest leak of classified files in American history.

But the trial is focused on whether Manning broke rules governing the use of his computer, violated the Espionage Act by leaking sensitive information that could harm US national security and had the intention of assisting Al-Qaeda through his disclosures.

Coombs said the government has not offered "any evidence" to show that Manning knew the leaked files could fall into the hands of Al-Qaeda militants.

To say that "he should have known" was not sufficient, Coombs said.

"There should have been something more than simply that," he said.

The judge has said the government must prove Manning had "actual knowledge" that his leak would aid the enemy, either directly or indirectly.

At Monday's proceedings, Coombs sought to counter the government's allegation that Manning committed committed computer fraud by downloading classified documents using a program known as Wget.

The defense says Manning already had access to the data he downloaded because of his job as an intelligence analyst and that he used the Wget program simply to speed up the download.

Manning, 25, faces a possible life sentence on the aiding the enemy charge and a total of more than 140 years if found guilty on all counts.

The prosecution rested its case after five weeks and the defense presented its case in three days of testimony last week.

The judge also is due to rule on the scope of the prosecution's planned "rebuttal" to the evidence put forward by the defense.

Manning has become a folk hero to his supporters who see him as a crusading whistle-blower trying to expose the excesses of US foreign policy.

But his critics say Manning betrayed his soldier's oath and portray him as a reckless traitor who undermined US diplomacy and endangered lives with his leak.