Russian officials have cast doubt on multibillion-dollar pledges to Venezuela touted by its president Nicolás Maduro, whose crisis-wracked country has become increasingly dependent on Moscow as its most prominent international supporter. Following a three-day visit to Moscow last week and meetings with dozens of Russia’s top officials, the Venezuelan leader boasted of $6bn worth of investment pledges and a string of other deals designed to help prop up its collapsing economy that has been savaged by hyperinflation, political crisis and US sanctions that have cut it off from the west.

The visit underscored Russia’s role as Venezuela’s lender of last resort and president Vladimir Putin as its key foreign backer— but made clear the limits of Moscow’s ability and desire to bankroll Mr. Maduro’s regime. Mr. Maduro said Moscow had pledged to invest $5bn in joint ventures in the country’s oil sector, $1bn in mining projects and to export 600,000 tonnes of wheat to Venezuela to cover its 2019 needs. He said that Russia had also agreed to modernize Venezuela’s armed forces and to look into potential projects in the country’s diamond industry. But following Mr. Maduro’s visit, Russian officials sought to damp expectations of any major financial support.

“This hardly sounds real,” said a person close to Rosneft, Russia’s state-controlled oil company that has investments in Venezuela. “Quite obviously Rosneft would have made a statement and bragged about a deal of that size had it really happened,” the person said. “Besides, the amount of investment in the joint oil projects Maduro named sounds suspiciously close to the amount in the existing deal,” they added. Rosneft has lent $6bn to Venezuela’s oil company PDVSA partly as pre-payment for crude, more than half of which remained outstanding as of the end of September. Mr. Maduro met with Igor Sechin, Rosneft’s chief executive, in Mosco