Russian President Vladimir Putin is planning to visit Saudi Arabia in October, Saudi Energy Minister Khalid Al Falih said on Monday.
Mr Al Falih, who was in Moscow for talks with Russian Energy Minister Alexander Novak, said Saudi companies were considering taking part in a methanol plant project in Russia's east, Interfax news agency reported.
The two were meeting for the sixth Russian-Saudi Intergovernmental Commission on Trade, Economic and Scientific and Technical Co-operation.
Mr Al Falih is also the chairman of Saudi Aramco, the state oil company that earned $111.1 billion (Dh408bn) in net income last year, making it the most profitable company in the world.
He said that Aramco was studying several Russian oil companies and projects in which it might be interested in investing.
Mr Al Falih said Russia’s Rosatom might be invited to take part in another round of bids to build nuclear plants in Saudi Arabia.
As a signatory to the 2015 Paris agreement on climate change, the kingdom is seeking cleaner energies such as solar, wind and nuclear, and move away from hydrocarbons.
Mr Putin made the first visit by a Russian president to Riyadh in 2007, when he met King Abdullah.
The two countries have long sought closer relations on oil, gas and energy co-operation.
Despite opposing views on the Syrian war, where Mr Putin has sent his military and air force to bolster Bashar Al Assad, and Riyadh being a key ally of Washington, the two countries have strong co-operation on issues such as Opec oil production quotas.
While Russia is not a member of Opec, a 2016 meeting between Mr Putin and Saudi Crown Prince Mohammed bin Salman led to an agreement to cut global oil production to boost prices after a large fall in 2014.
As the world's largest oil exporter, Saudi effectively leads the international bloc.
The agreement to curb production is between Opec and non-member states led by Russia in an alliance that is informally known as Opec+, which comprises 24 producers.
In Moscow on Monday, Mr Al Falih said he had constructive talks with Russian officials about co-operation between Opec and non-bloc members.
But Russia was undecided about whether to prolong the output curbs that expire at the end of this month, Mr Al Falih said.
"So, I think the remaining country to jump on board now is Russia. I will wait for the Russian dynamics to work themselves out," he told Russia's Tass news agency.
"There is a debate obviously within the country about the exact volume that Russia should be producing in the second half."
In 2017, Russia and Saudi Arabia also announced a plan to set up a $1bn energy fund as part of a bid to cement a partnership between the world's two largest oil producers at that time.
Mr Putin and Prince Mohammed have a good working relationship and were seen at the G20 summit in Buenos Aires, Argentina, in November last year giving high-fives and embracing warmly.