Russia and Saudi Arabia will sign joint investment agreements worth more than $3 billion during the visit, Russian Energy Minister Alexander Novak was quoted as saying on Wednesday.

"I think these fundamental mutual interests will sooner or later change the nature of Russian-U.S. relations for the better", Putin said.

We intend to develop bilateral relations for development of global economy with peace and security.

According to Mercouris, Russia "is able to help the Saudis on questions like oil, like Syria, like future relations with the other countries in the region with which Saudi Arabia has so many difficulties". "Today we alone as the Russian Direct Investment Fund announced deals worth Dollars 2.1 billion", said Kirill Dmitriyev, the head of the fund set up to attract investment.

The visit comes after decades of tensions, most recently over the war in Syria, where Saudi Arabia had backed the Sunni rebels fighting to oust President Bashar Assad, while Iran had teamed up with Russian Federation to strengthen his control. In coming period, cooperation between two countries is expected to strengn in field of defence industry.

Saudi Arabia's King Salman arrived in Moscow on Wednesday, the first official visit to Russian Federation by a ruler of the conservative kingdom.

The two leaders exchanged views on the situation in the Middle East and North Africa and agreed on the need to fight terrorism, Lavrov said.

Another memorandum of understanding was signed under which Sibur, Russia's largest producer of petrochemicals, would explore cooperation with Saudi Arabia.

President Vladimir Putin hailed the visit by the 81-year-old king as a "momentous" event, reported Russian state news agency RIA Novosti.

"Yes, we had a couple of phone conversations on various issues of mutual interest, including Syria", Putin said.

Another potential point of disagreement between Riyadh and Moscow could be Yemen, where a Saudi-led coalition has been bombing Huthi rebels since 2015, drawing criticism from Moscow.

He also said the two agreed on the importance of fighting terror and of finding peaceful solutions to conflicts in the Middle East.

Chechen President Ramzan Kadyrov welcomed King Salman's visit, posting on his Instagram account: "Welcome to Russian Federation".

The price of oil collapsed from near $120 a barrel in June 2014 due to weak demand, a strong dollar and booming USA shale production.