Investing.com - Crude prices firmed on Friday after the West slapped fresh sanctions on Russia for annexing Crimea, which sparked fears escalating geopolitical tensions may threaten Russian oil exports.
On the New York Mercantile Exchange, West Texas Intermediate crude for delivery in May traded at $99.87 a barrel during U.S. trading, up 0.98%. New York-traded oil futures hit a session low of $98.26 a barrel and a high of $100.25 a barrel.
The May contract settled down 0.27% at $98.90 a barrel on Thursday.
Nymex oil futures were likely to find support at $98.10 a barrel, Thursday's low, and resistance at $102.89 a barrel, the high from March 7.
The European Union and the U.S. intensified sanctions against Russian President Vladimir Putin and his allies to pressure his government to defuse the global standoff over Ukraine.
Western nations added new names to their lists of Russians and Ukrainians punished with asset freezes and travel bans.
Russia followed suit with similar sanctions, and while viewed by markets as a tit-for-tat measure, oil prices rose on concerns diplomatic efforts to diffuse the crisis may be unraveling.
Elsewhere, bottom fishing sent oil prices rising as well, mainly after the U.S. dollar cooled its gains.
The dollar posted strong gains this week after Federal Reserve Chair Janet Yellen suggested at a Wednesday press conference that benchmark interest rates could rise six months after the Fed's bond-buying program ends, which is widely seen taking place this fall.
Fed asset purchases, currently set at $55 billion a month, aim to stimulate the economy by suppressing interest rates, weakening the dollar as long as they remain in effect, and Yellen's comments left many expecting benchmark interest rates to begin rising around the first half of 2015.
Profit-taking sent the dollar falling on Friday, which gave oil room to rise.
A weaker greenback often makes oil an attractive buy on dollar-denominated exchanges.
Elsewhere, on the ICE Futures Exchange in London, Brent oil futures for May delivery were up 0.70% and trading at US$107.20 a barrel, while the spread between the Brent and U.S. crude contracts stood at US$7.33 a barrel.