Russia's National Wealth Fund (NWF) stood at the equivalent of $153.1 billion as of June 1, Russia's finance ministry said on Friday, slightly down from $155 billion on May 1.

The finance ministry said the sovereign wealth fund was equivalent in value to 8.2% of Russia's gross domestic product (GDP), down from 8.3% a month earlier.

The NWF is a rainy-day fund built up from years of profits on oil and gas exports.

The finance ministry said it had spent 49.0 billion roubles ($607.1 million) of yuan and gold from the NWF during May to cover the government's budget deficit. It plans to spend 2.9 trillion roubles from the NWF this year.

The fund's liquid assets amounted to 6.64 trillion roubles, or 4.4% of GDP, by early May, compared with 6.83 trillion roubles, or 4.6% of GDP, a month earlier.

In the first five months of the year, the finance ministry has spent 439.5 billion roubles covering the budget deficit.

($1 = 80.7100 roubles) (Reporting by Darya Korsunskaya; Writing by Alexander Marrow Editing by Gareth Jones)