A US Treasury official pushed back against speculation that Russia — confronted by a set of price caps and sanctions that seek to limit its oil revenue — could be quietly earning more than reported data suggest.

“To my knowledge. there is no hard data or conclusive evidence that supports speculation about Russia evading the sanctions by using coalition service providers and receiving above-the-cap payments,” Ben Harris, the Treasury’s assistant secretary for economic policy, said Thursday, according to the text of remarks he’s scheduled to deliver in Houston.

Pricing data from Platts, a unit of S&P Global, suggest traders are garnering an unusually large margin on shipments of Urals crude sent from Russia’s ports in the Baltic region to India’s west coast, with delivery prices more than $20 a barrel higher than the purchase amounts.

Analysts at Goldman Sachs, in a Feb. 10 note to clients, said the effective price of Russian oil may be far higher than what’s often reported, and that might help explain why Russian oil production has remained resilient.

The US-led coalition that has imposed the price caps has offered no objection to high margins for intermediaries. But if Russian revenues were higher than reported, that would undermine claims of the price cap’s effectiveness and could be evidence of price-cap violations. 

Buyers of Russian oil are prohibited from accessing Western maritime services, like insurance, unless their shipments are priced below caps set by the US and its allies.

While Russia’s exact take on every shipment isn’t known, Harris said in an interview with Bloomberg News before his speech that Russia’s overall revenue from oil sales since the cap was instituted had declined, that Russian production had remained relatively constant and that global prices had remained stable, despite what many skeptics had predicted.

“None of those are in dispute,” he said.

Moscow spurred a minor bump in global crude prices Feb. 10 when Deputy Prime Minister Alexander Novak announced Russia would lower production by 500,000 barrels a day next month. Brent rose by more than 2% on the day to $86.39 a barrel but has since retraced much of that.

Harris, in the interview, downplayed the cut, saying it had little impact on global prices.

In his speech, at a conference hosted by Argus Media, Harris began with a note of caution on assessing the price cap’s achievements. 

“Success remains to be seen and we continue to approach the implementation of this policy with humility,” he said.

At the same time, senior Russian officials “have openly acknowledged that the price cap is hurting their ability to fund their war and prop up the Russian economy,” Harris said.