BEIJING -- Russia has become China's largest source of oil as Beijing and Chinese companies stepped in to fill the gap left from biting Western sanctions.
China imported 8.4 million tonnes of oil from Russia in May -- -- a 55% on-year rise -- compared with 7.8 million tonnes from Saudi Arabia, according to data released on June 20 by China's General Administration of Customs.
The volume of Russian oil exports to China grew by 28% from the previous month, hitting a record level and handing the Kremlin $5.7 billion in revenue.
In total, China bought $7.47 billion worth of Russian energy products in May, about $1 billion more than in April, according to Bloomberg News.
This source of income has been vital to the Kremlin as it continues its brutal invasion of Ukraine, and as Russian President Vladimir Putin likens himself to Peter the Great, who expanded the Russian empire in the 18th century.
Chinese President Xi Jinping on June 15 assured Putin of China's support on Russian "sovereignty and security".
China has refused to condemn Moscow's massive military assault on Ukraine and has been providing diplomatic cover for Russia by blasting Western sanctions and arms sales to Kyiv.
China is "willing to continue to offer mutual support [to Russia] on issues concerning core interests and major concerns such as sovereignty and security", state broadcaster China Central Television (CCTV) reported Xi as saying during a call with Putin.
It was the second reported call between the two leaders since Putin launched his invasion of Ukraine on February 24, which has killed thousands and displaced millions.
Xi praised the "good momentum of development" in bilateral relations since the start of the year "in the face of global turmoil and changes", according to CCTV.
Beijing is willing to "intensify strategic co-ordination between the two countries", Xi reportedly said.
The Kremlin said the two leaders had agreed to ramp up economic co-operation.
"It was agreed to expand co-operation in the energy, financial, industrial, transport and other areas, taking into account the situation in the global economy that has become more complicated due to the unlawful sanctions policy of the West," the Kremlin said following the phone call.
'Wrong side of history'
The United States swiftly responded with a frosty retort to Beijing's expressed alignment with Moscow.
"China claims to be neutral, but its behaviour makes clear that it is still investing in close ties to Russia," a State Department spokesperson said in a statement.
"China has already made a choice," the statement continued.
Nearly five months into Russia's war in Ukraine, "China is still standing by Russia. It is still echoing Russian propaganda around the world. It is still shielding Russia in international organisations... And it is still denying Russia's atrocities in Ukraine by suggesting instead that they were staged," it said.
"Nations that side with Vladimir Putin will inevitably find themselves on the wrong side of history."
"This is not a moment for equivocation or hiding or waiting to see what happens next. It is already clear what is happening," the statement concluded.
The West has imposed unprecedented sanctions on Russia in retaliation for its invasion of Ukraine, and Moscow accuses Europe and the United States of thereby causing a global economic slowdown.
Moscow is also looking for new markets and suppliers to replace the major foreign firms that left Russia following the invasion.
The European Union and the United States have warned that any backing from Beijing for Russia's war, or help for Moscow to dodge Western sanctions, will damage ties.
'No limits' friendship
Once bitter Cold War enemies, Beijing and Moscow have stepped up co-operation in recent years as a counterbalance to what they see as US global dominance.
The pair have drawn closer in the political, trade and military spheres as part of what they call a "no limits" relationship.
This month they unveiled the first road bridge linking the two countries, connecting Blagoveshchensk, Russia, with Heihe, China.
The leaders' call June 15 fell on Xi's 69th birthday and was their first reported communication since the day after Russia invaded Ukraine.
Beijing is Moscow's largest trading partner, with trade volumes last year hitting $147 billion, according to Chinese customs data.