King Salman of Saudi Arabia will arrive in Russian Federation later Wednesday for the first official visit to the country by a Saudi king.
The two countries have already struck a deal on weapons sales and leaders discussed the oil market and Syrian crisis.
While they are partners on the oil market, on the foreign policy front, Moscow and Riyadh land on opposite sides of the Syrian conflict, with Russian Federation supporting the regime of Bashar al-Assad while Saudi Arabia supports his opposition.
A thaw between Moscow and Riyadh helped reach November's deal in which Opec and 10 other oil-producing countries, including Russian Federation, agreed to cut their production in a bid to combat a supply glut and shore up crude prices.
Russian Federation has prepared a package of around US$3.5 billion arms sales to Saudi Arabia, which includes several divisions of S-400 anti-aircraft missile systems.
"Putin and Salman will most likely reach, but not announce, an agreement to extend the OPEC/non-OPEC production deal, though with a commitment to taper the cuts", said Eurasia Group.More news: Erin Lee Macke Left 4 Kids Home Alone, Took Off for Europe
"Is there anything in the world that stays unchanged?"
"We have many options for Venezuela, including a possible military option if necessary", Trump said.
"The Saudis want help on Iran, and Russia wants trade and investment", said Mark N. Katz, a Russia-Middle East relations analyst at George Mason University.
Briefing the media on the talks between Putin and King Salman, Russian Foreign Minister Sergey Lavrov focused on the common ground between the two countries.
Chechen President Ramzan Kadyrov welcomed King Salman's visit, posting on his Instagram account: "Welcome to Russian Federation".
"Saudi Arabia has recognised Russian Federation as a significant player in a region that is important to it", he said.
Still, Russia doesn't have the capacity to replace the USA as Saudi Arabia's main ally, Anna Borshchevskaya, a fellow at The Washington Institute for Near East Policy, told the Associated Press.
There has been no immediate US reaction to the growing ties between Riyadh and Moscow.