KYIV, July 14 - A panel of Ukrainian judges overturned a decree by President Volodymyr Zelenskiy dismissing the head of the Constitutional Court, prompting the president's office to say Zelenskiy would appeal, Reuters reported.

Zelenskiy issued a decree in March dismissing Oleksandr Tupytskyi, who had opposed some anti-corruption reforms. Zelenskiy called the judge's actions a threat to national security.

A panel of judges from Ukraine's Supreme Court overruled Zelenskiy's decision on Wednesday, saying the decree firing Tupytskyi violated "the guarantees of independence and immunity of a judge of the Constitutional Court of Ukraine established by the constitution and laws of Ukraine".

The panel said its decision could be appealed to the Supreme Court's Grand Chamber, its highest body. The president's office said Zelenskiy would lodge such an appeal: "The President of Ukraine will use all constitutional mechanisms in order to protect the reform process in our state".

Tupytskyi said he trusted the Grand Chamber to resolve the issue: "I believe the Supreme Court will be impartial when (further) considering the case," he wrote, responding to Reuters' requests for comment.

He has previously accused Zelenskiy of trying to engineer a "constitutional coup" by removing him.

The Constitutional Court under Tupytskyi struck down some anti-corruption laws in October, ruling that a proposed punishment for officials who make false asset declarations was excessive, and blocking some powers of the main NAZK anti-graft agency.

The ruling caused a long delay in the disbursement of new loans from Ukraine's international supporters, including the International Monetary Fund, which had demanded the reforms as a condition of lending. Parliament later restored some of the legislation.

Restoring all anti-corruption measures is a key condition of unlocking more loans under a $5-billion stand-by program approved by the IMF in 2020. Ukraine has received only one tranche since then. (rt/ez)