Russia's foreign minister on Thursday urged against "unfounded allegations" about a recent drone attack on oil facilities in Saudi Arabia.
Such rhetoric only escalate the situation in the region, already torn by numerous conflicts, said Sergey Lavrov at a news conference in Moscow.
"As far as I understand, efforts [on conducting an impartial investigation] are now being made. It is important so that it would be really impartial process, because unfounded accusations do not help to solve the problem, but escalate the situation in the region, where everything is already too confrontational," said Lavrov.
Earlier, an unnamed source in the Russian Defense Ministry told reporters that U.S. Patriot and Aegis air defense systems were unable to repel the drone attacks due to "low efficiency against miniature aerial targets and cruise missiles".
On Saturday, drones hit two Aramco units in the north of Saudi Arabia in an attack claimed by Houthi rebels in Yemen.
Since 2015, the Saudi-led coalition has been fighting the Iran-backed Houthi rebels in Yemen. Thousands of Yemenis were killed and the country was pushed to the brink of famine.
In recent months, Houthis, whose mid and long-range ballistic missiles are usually intercepted by Saudi air defense systems, have targeted certain strategic parts of Saudi Arabia with armed drones.
By Elena Teslova in Moscow