Ukrainian President Volodymyr Zelensky has convened an urgent meeting of the National Security and Defense Council (NSDC) behind closed doors over the notorious ruling by the Constitutional Court that affects the country's anti-corruption reform.

"President of Ukraine Volodymyr Zelensky has convened an urgent closed meeting of the National Security and Defense Council to determine measures for the state's urgent proper response to new threats and challenges to national security and defense," press service of the President's Office said on its website on October 29.

"The devastating 'blows' being inflicted on the country's achievements in the field of combating and effectively responding to corruption in Ukraine must not be ignored. We need an immediate and rigorous assessment of the decisions of individual actors, whose actions are becoming increasingly socially threatening," the press service quoted Zelensky as saying.

Recently, there have been signs that "certain bodies are trying to revise key parts of Ukraine's public contract that ensure zero tolerance for corruption and any form of opacity in public administration," the report said.

"This is unacceptable," the statement added.

The president is expected to invite NSDC members to discuss the situation as regards national security and pass appropriate decisions.

Read alsoEU hints at possible aid cut over Constitutional Court rulingMoreover, bills will be drafted to prevent similar crises. Following that, the head of state will submit the relevant draft laws to the Verkhovna Rada, Ukraine's parliament, as urgent ones.

Constitutional Court vs anti-corruption reform

On September 16, the Constitutional Court ruled unconstitutional certain provisions of the law on the National Anti-corruption Bureau.

These included the norms on empowering a President to establish NABU, appoint and dismiss its director,  appoint three members to the competition commission selecting the Bureau chief, appoint one member of the external control commission to conduct an independent audit of NABU performance, its operational and institutional independence, and approve the regulation on the Civil Control Council and the procedure for its formation.

Also, on July 28, the CSU declared unconstitutional the Presidential Decree of April 16, 2015, on the appointment of Artem Sytnyk as NABU Director. The relevant motion filed to the CCU by 51 lawmakers claimed the then head of state Petro Poroshenko went beyond his constitutional powers and violated the ban on usurpation of state power. Also, the deputies argued, the decree contradicts Constitutional provisions on the exhaustive list of presidential powers.

Read alsoZelensky's envoy to Constitutional Court comments on asset declaration rulingOn October 27, the Constitutional Court ruled on the case on the motion submitted by 47 legislators to repeal Article 366-1 of the Criminal Code, which provides for liability for inaccurate asset declaration by government officials.

On October 28, pursuant to the CCU ruling, the National Agency on Corruption Prevention shut down public access to the Unified State Register of Asset Declarations.