TOKYO, Feb 21 (Reuters) - Most of the Japanese companies surveyed by the Japan External Trade Organization (JETRO) stuck to their earlier decisions to partially or fully suspend operations in Russia following its invasion of Ukraine two years ago, JETRO said on Wednesday.

Japan, a member of the Group of Seven developed nations, has joined Western sanctions on Russia after Moscow has started a war on Ukraine in February 2022 but has kept stakes in some of the energy projects as a matter of energy security.

In early February, JETRO conducted a survey of 156 companies operating in Russia's two biggest cities, Moscow and St Petersburg. Of the 63 firms that responded 60.3% have partially or fully suspended business in Russia, the survey showed.

The number of those with fully or partially suspended operations, however, decreased by 5.9 percentage points from JETRO's previous survey in May 2023.

Among those 60.3%, operations were fully suspended by 25.4%, an increase of 9.2 percentage points. The share of companies doing "business as usual" rose by 4 percentage points to 34.9%, JETRO said, without naming the companies.

Those continuing business as usual have diversified payment methods and currencies, reviewed their business partners and products to avoid sanctions, the survey showed.

"Companies that continue to do business in Russia said that they decided to stay because of favourable market conditions, expectations for the future resumption of business between Japan and Russia, and expectations for the growth potential of the Russian market," JETRO said in the survey.

Among reasons for business suspension were reputation risks, sanctions and change of the headquarter's approach towards Russia. Those withdrawing are transferring or selling their operations to local investors, the survey said.

Some of the companies still have one or more expatriates in Russia while some have staff operating outside of the country, according to JETRO.

(Reporting by Katya Golubkova, additional reporting by Kaori Kaneko Editing by Tomasz Janowski)