* Russia's outstanding foreign debt seen shrinking further
* Low oversupply risks could boost demand for high-yielding bonds
* Market reaction to latest U.S. sanctions short-lived
MOSCOW, Aug 10 (Reuters) - Far from taking a big hit from the latest round of U.S. sanctions, Russian securities denominated in foreign currency may see a surge in interest from investors if the curbs further crimp debt sales from companies.
Russian firms have ventured back to global bond markets this year in greater numbers compared to previous years raising $15 billion by end-July, according to Thomson Reuters data.
But overall, they are still repaying more than they are borrowing -- investment bank VTB Capital calculates $20 billion in Russian private sector Eurobonds mature in 2017, of which $5.4 billion is due between now and year-end.
In total, including the sovereign, Russian Eurobond repayments total around $150 billion over the next seven years, as this chart shows:
But hard currency borrowing from Russia has declined since 2014, when Western sanctions were first imposed due to Russia's annexation of Crimea and its support of anti-Kiev rebels in eastern Ukraine.
Limited market access means less borrowing -- a positive for the prices of existing securities.
"Russia is a benign story -- supply risk is very low," said Chris Perryman, a portfolio manager at PineBridge Investments in London.
"Some of the debt is coming due for sanctioned banks and corporates but they will have to find the funding elsewhere. So you will see money come into the market from dollar maturities but no more issuance."
Bonds maturing by year-end include a $600 million issue by state-run bank VEB and $1.2 billion bond by Russian Agricultural Bank. Both are under sanctions, which limits their ability to refinance debt on global capital markets.
Another bond, from steelmaker Severstal, is expected to be redeemed from the company's cash reserves.
Perryman said sanctions-led scarcity would further burnish the appeal of high-grade Russian names.
"There are a few high quality names in Russia such as Lukoil and NLMK which have very low leverage and in any other zip code they would be trading with lower yields. But here, they are capped by the sovereign ceiling," Perryman said.
Lukoil, Russia's second-largest oil producer, issued two Eurobonds in 2013, a year before sanctions, and then tapped the Eurobond market again only in Oct. 2016.
Steel producer NLMK also placed a Eurobond in 2013, returning to the global markets only in mid-2016.
In contrast with the corporate sector, bonds of Russian private banks are likely to underperform as the sector is pressured by the uncertainty related to an ongoing purge of the banking sector -- so far this year the central bank revoked nearly 50 licences.
An official at one of Russia's largest oil producers, which has a long track record of borrowing abroad, told Reuters that the company had been increasing borrowing at home for some years.
"Our lawyers scrutinised sanctions and did not get excited ... For now, it seems that nothing has changed for us," said the official, who asked not to be named.
Rouble debt and the currency suffered a short-lived wobble after the latest sanctions round, with 10-year yields hitting three-month highs and the currency slipping to 60.85 against the dollar from 59.7 seen the day before.
But those fears appear to be receding. JPMorgan said this week it was returning to an overweight position on the rouble and Russian government bonds.
(Additional reporting by Olesya Ostakhova and Kira Zavyalova in Moscow; Editing by Catherine Evans)