In August, Royal Mail said it had been notified by Kwasi Kwarteng, the then minister for business, energy and industrial strategy, that he was exercising his powers to look into Kretinsky's vehicle VESA Equity Investment's (VESA) proposals under the National Security and Investment Act.

The act came into force this year to give the government greater say over deals where national interests might be involved.

VESA, ultimately controlled by Kretinsky and his business partner Patrik Tkac, in August had separately said it had voluntarily contacted the government to inform it of its intention to increase its stake in Royal Mail, currently just over 22%.

On Monday, International Distributions Services said it had been notified by the Secretary of State for Business, Energy and Industrial Strategy that no further action is to be taken under the NSI Act in relation to VESA potentially increasing its stake in the company to more than 25%.

Kretinsky, who built one of Europe's largest energy groups, EPH, has stakes in Le Monde newspaper, French retailer Casino, British supermarket group Sainsbury and French TV group TF1, among others.

The office of the Secretary of State for Business, Energy and Industrial Strategy and VESA - Royal Mail's top shareholder - did not immediately respond to Reuters' requests for comment.

The review in August had come days after the government decided not to take action over billionaire Patrick Drahi's stake in British telecoms company BT Group, which it had also examined under the new act.

(Reporting by Chandini Monnappa and Aby Jose Koilparambil in Bengaluru; Editing by Krishna Chandra Eluri)