By Adam Easton BBC, Vilnius

Opinion polls show Mr Paksas is popular despite the allegations

Mr Paksas is already facing impeachment proceedings in parliament after his office was accused of having links to Russian crime gangs.

But he insists he has done nothing wrong and refuses to resign.

The court may take up to three weeks to decide on the six charges levelled at Lithuania's president.

Among the charges, Mr Paksas is accused of posing a threat to national security, leaking state secrets and allowing his aides to abuse their office.

Parliamentarians hope the court's ruling will simplify the impeachment trial which started last week before being adjourned.

Embarrassed

Lithuania's highest court has already ruled Mr Paksas violated the constitution once when he awarded citizenship to a controversial Russian businessman who was the main sponsor of his election campaign.

Parliamentarians say a final impeachment vote may be taken next month before Lithuania joins the European Union on 1 May.

The scandal's timing could not have been more embarrassing for the Baltic nation.

A twice former prime minister, Mr Paksas says the accusations are a plot by his political enemies.

In recent months the 47-year-old president has been touring the country, rallying his supporters.

He has said he would stand for re-election should he be impeached, as the constitution allows him to.