SINGAPORE, Nov 18 Reuters Oil prices edged up on Monday after fighting between Russia and Ukraine intensified over the weekend, although concerns about fuel demand in China, the world39;s secondlargest consumer, and forecasts of a global oil surplus weighed on markets.

Brent crude futures gained 18 cents, or 0.3, to 71.22 a barrel by 0713 GMT, while U.S. West Texas Intermediate crude futures were at 67.08 a barrel, up 6 cents, or 0.1.

Russia unleashed its largest air strike on Ukraine in almost three months on Sunday, causing severe damage to the country39;s power system.

In a significant reversal of Washington39;s policy in the UkraineRussia conflict, President Joe Biden39;s administration has allowed Ukraine to use U.S.made weapons to strike deep into Russia, two U.S. officials and a source familiar with the decision said on Sunday.

There was no immediate response from the Kremlin, which has warned that it would see a move to loosen the limits on Ukraine39;s use of U.S. weapons as a major escalation.

Biden allowing Ukraine to strike Russian forces around Kursk with longrange missiles might see a geopolitical bid come back into oil as it is an escalation of tensions there, in response to North Korean troops entering the fray, IG markets analyst Tony Sycamore said.

Saul Kavonic, an energy analyst at MST Marquee, said So far there has been little impact on Russian oil exports, but if Ukraine were to target more oil infrastructure that could see oil markets elevate…