Brno, Czech Republic - The Czech Republic's Constitutional Court ruled Wednesday that the European Union's reform treaty is in tune with Czech law, unblocking its ratification in the last EU member to vote on the treaty, court chairman Pavel Rychetsky said.

The decision by the 15-member court enables the country's bicameral parliament to consider the Lisbon Treaty before the Czech Republic assumes the rotating six-month EU presidency on January 1.

The Constitutional Court however reviewed only elements of the treaty put under its review by eurosceptic members of the parliament's upper house.

The move opens the door to a new, later complaint, potentially by Czech President Vaclav Klaus, a vocal critic of the treaty and of deeper European integration.

The ruling does not oblige Klaus to sign the treaty if ratified by lawmakers.

The president, who attends the hearing, has said earlier that he would not block the treaty but sign it after Ireland reverses its rejection. He is given no time limit for approving the treaty after it clears parliament.

Klaus argued before the court on Tuesday that the treaty was at odds with the Czech constitution as it infringes on the country's sovereignty.

The court countered in its ruling Wednesday that EU integration was not taking place "in a radical manner that would translate into a loss of sovereignty but it is an evolutionary process", Justice Vojen Guttler said.

The pact, aimed at streamlining the decision-making in the enlarged 27-member EU bloc, has been stalled since Irish voters turned it down in a June referendum.

While at the helm of the EU, the Czech Republic is likely to negotiate with Ireland on ways to overcome the rejection.

Ireland was the only member state that called a public vote on the accord, which must be approved by all EU members to become valid. (dpa)