Saudi Arabia's de facto ruler, Crown Prince Abd Allah bin Abd al-Aziz, wound up a historic three-day visit to Russia on Thursday by signing a five-year oil and natural gas accord.

The visit, the first by a Saudi ruler since 1926, marks a rapprochement between the two countries who, between them, control a substantial proportion of the world's hydrocarbon resources.

The Russian business daily, Kommersant said Saudi investment in Russia, resulting from an improvement in relations, "could lead to a huge leap forward for Moscow" in the energy sector.

American concerns

Moscow is angling for a share in the development of Saudi Arabia's huge reserves, and is also seeking investment in its own oil and gas industry.

But officials in Moscow were at pains to ensure the pact was not seen in Washington as a deal aimed at securing control over the international oil and gas market.

"It does not look like we are talking about an anti-American plot. At least, Moscow is doing everything it can to make sure that this is not (how it) is being interpreted by our Western partners," Kommersant reported.

Saudi Arabia sits on about a quarter of the world's known oil reserves, and Russia is the biggest oil exporter outside the Organisation of Petroleum Exporting Countries (OPEC).

Oil prices

This means the two producers' combined weight could enable them to exercise a predominant influence on global oil prices.

Prince Abd Allah's visit to Russia
is the first by a Saudi ruler since
1926

Saudi Oil Minister, Ali Ibrahim Naimi, noted the current state of the oil market served as proof of the two countries' success at keeping it stable.

His Russian counterpart Igor Yusufov agreed.

"We feel ourselves responsible for the world market's stability. So the signing of our cooperation accord was quite timely," he said.

Mutual mistrust

Prince Abd Allah's visit also signals a marked improvement in Russo-Saudi relations after decades of coolness arising from Saudi mistrust regarding Moscow's ambitions in the Islamic world.

Recently, Russia also accused Saudi Arabia of turning a blind eye to Muslim charities' funding of Chechen separatists.

Moscow only reopened its embassy in Riyadh in 1991, and even in 2002 trade between the two countries was still worth less than 67 million dollars.

However, relations have improved gradually, and the Saudi estrangement with the United States over the September 11 attacks appears to have accelerated the process.

Islamic world

Russian officials stressed the importance of the Saudi visit as a key step in Moscow's wide-ranging approach to better relations with the Islamic world.

This was highlighted last month when President Vladimir Putin said Russia planned to join the Organization of the Islamic Conference.

Riyadh will back Moscow's application to become an affiliate member, a Russian diplomat said on Thursday, citing the "understanding" expressed by Saudi officials.