TOKYO (Reuters) - A Japanese health ministry panel recommended approval of the COVID-19 antiviral pill developed by Merck & Co Inc on December 24, part of plans by Prime Minister Fumio Kishida to roll out new treatments by yearend as concerns rise about the Omicron variant.

The panel decision sets the stage for shipments of 200,000 doses across the country from this weekend, based on preparations announced earlier by Kishida.

Japan is betting heavily on oral treatments to keep serious infections and deaths at bay should a feared sixth wave of the pandemic emerge. The government agreed last month to pay Merck and its partner Ridgeback Biotherapeutics about $1.2 billion for 1.6 million courses of their drug molnupiravir.

In addition, Kishida announced last week a deal to procure 2 million doses of a separate antiviral pill developed by Pfizer Inc. And Japan's Shionogi & Co is expected to soon file for approval of its own treatment, supplying another 1 million doses by early next year.

U.S. regulators on Thursday authorized the Merck pill for certain high-risk adult patients.

Countries rushed to buy Merck's molnupiravir after very promising initial results, but subsequent company data in late November indicated the drug was markedly less effective than previously thought.

Japan this week confirmed the first known cases of Omicron infections that could not be traced back to overseas travelers. Community transmissions of the variant have now been found in the western cities of Osaka and Kyoto, and a suspected case was announced in Tokyo on Friday.