The September surplus with the USA was larger than China's overall trade surplus of $31.69 billion for the month.
Yi told an investment audience on Thursday that China's monetary policy was on an opposite cycle to that of the Federal Reserve, which has been raising rates amid a strong economy, people who attended the closed-door session said.
"Exports continued to defy USA tariffs last month but imports struggled in the face of cooling domestic demand", said Julian Evans-Pritchard of Capital Economics in a report.
"China-US trade friction has caused trouble and pounded our foreign trade development", customs spokesman Li Kuiwen told reporters Friday.
"I think it's pretty clear that if there is an IMF program, that we'd need to make sure those funds are used for appropriate purposes and they're not being used to repay China or other creditors".
But it was still too early to see the impact of the tariffs, said Julian Evans-Pritchard, China economist at Capital Economics, a consultancy.
Chinese refiners are buying more and more very cheap heavy Canadian crude oil to make up for the dwindling supply of Venezuela's heavy grades as China's road construction sector-a key consumer of the heavy oil's bitumen yield-is booming.
They are also promoting settlements in rubles and yuan, bypassing the U.S. dollar and other Western currencies.
U.S. Vice President Mike Pence also accused Beijing last week of seeking to interfere in the U.S. midterm elections to be held next month.
Trump and Chinese president Xi Jinping have agreed to meet next month at the G-20 summit in Buenos Aires, in hopes of resolving their intensifying trade conflict. That designation would be a first for China and would trigger a process that could lead to punitive steps after a series of talks.
"Bullying might be effective for small economic entities, but it will not be effective against a big economic power", Yu wrote in a column published Friday in the state-run China Daily.
China is not backing down as tensions escalate with the U.S., issuing a mock-proposal yesterday that the trade deficit would be easily closed if America sold expensive military equipment to Beijing.
President Trump added he could do a lot more if he wanted to, but said he would prefer Beijing come to the negotiating table.