By Cassie Werber 

LONDON--European and U.S. benchmark crude oil prices headed in different directions Wednesday, as they reacted to the new round of sanctions on Russia.

The U.S. government followed the EU yesterday, expanding sanctions on Russia to include the energy, finance and defense sectors.

In Europe, traders saw little threat to supplies from Russia, which needs the money from oil sales, and Brent prices fell. ICE September crude was down 0.21% at $107.49 a barrel.

In the U.S., however, WTI traders focused on low stocks at the major storage point in Cushing, Oklahoma, said David Hufton of brokerage PVM. WTI crude on the Nymex exchange was up 0.33% at $101.30 a barrel Wednesday morning.

"The fact is we have two crude price markers, sometimes responding to the same factors and at other times to factors local to themselves," said Mr. Hufton.

Brent has continued to suffer withdrawal because threats to Russian and Iraqi supplies are growing more distant, and on the prospect of additional Libyan and Nigerian supplies, he said.

Commerzbank analysts said Brent's reaction was muted because the market isn't concerned about supply. "There is very little chance of Russia responding to the West's sanctions by curbing its oil shipments, since the country is too heavily reliant on the revenues generated by the oil export business," they wrote in a note to clients.

But a longer-term perspective may provide a different picture. "In the medium to long term, however, the oil supply from Russia could decline on the back of lacking investment, which would probably result in rising oil prices," they said.

The differing reactions mean that the "spread," or price difference between the two benchmark crudes, is the widest in almost a month.

Recently the ICE's gas oil contract for August delivery was up 50 cents at $894.50 a metric ton, while Nymex gasoline for September delivery was down 30 points at $2.8422 a gallon.

Write to Cassie Werber at cassie.werber@wsj.com

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