Russia is in talks with Iran over a $10 billion arms deal in which Moscow would provide advanced tanks, artillery systems, planes and helicopters to the Islamic republic.

The nascent deal would further cement an alliance between Moscow and Tehran that is likely to prove a major stumbling block for any rapprochement between Vladimir Putin and Donald Trump, who has vowed to rip up a nuclear agreement with Iran that the Kremlin supports.

“These talks are ongoing, the ground has been prepared, the portfolio amounts to around $10 billion,” Viktor Ozerov, an MP who heads the security and defence committee in the Federation Council, Russia’s upper house, told Russian reporters during a trip to Tehran on Monday.

He gave few details about the order, but said it would include Russia’s mainstay T-90 tank.