Global crude prices fell to the lowest level in more than two weeks Monday after sanctions announced by the U.S. and European Union against Russia were less aggressive than expected.

Brent crude for delivery in June fell $1.46, or 1.3%, to $108.12 a barrel on the ICE Futures Europe exchange, the lowest settlement since April 11. The market was up in early trade but began falling shortly before the sanctions were announced and continued to slip further throughout the day. Brent prices have fallen 2% in the past two trading sessions.

Prices for the benchmark U.S. contract flipped between gains and losses all day before settling 24 cents higher at $100.84 a barrel on the New York Mercantile Exchange.

The U.S. froze the assets of seven Russian officials and 17 companies and prohibited the officials from receiving U.S. visas. The individuals and companies were thought to be closely linked to Russian President Vladimir Putin. The European Union also imposed new sanctions on 15 Russian and Ukrainian individuals. The announcements came as the situation in Ukraine continued to deteriorate, with pro-Russian separatists taking hostages in recent days and the mayor of an eastern Ukrainian city shot by a sniper while jogging on Monday. The mayor was rushed to a local trauma center for surgery and was in serious condition.

Among those personally targeted by the sanctions was Igor Sechin, the president and chairman of Russian state oil company Rosneft, but the company itself wasn't targeted. Analysts had been watching to see whether major players in the oil market might be hit by the sanctions and what ripple effects that might have for prices if their participation were curtailed, but since they escaped sanctions for the moment the potential for disruption appeared limited.

"We're just slapping Russia with wet noodles," said Philip Verleger, an oil economist and consultant. "Unless we do something stronger, what we're saying is Russia is free to take what it wants."

Analysts and investors have also been waiting to see whether Morgan Stanley's deal to sell its physical oil franchise to Rosneft might be affected. In an interview on Bloomberg television Monday, Morgan Stanley chief financial officer Ruth Porat said the deal remained on track to close in the second half of 2014.

News that Libya's Zueitina oil terminal could resume operations in the near future also provided a bearish note to the market. Libya's oil shipments would add to already abundant global supplies.

A factor weighing on the U.S. market is the high level of domestic crude inventories, with stockpiles hitting an all-time record of 397.7 million barrels last week, according to the U.S. Energy Information Administration. Analysts said the glut is beginning to be reflected in prices paid for physical crude on the U.S. Gulf Coast with the expiry of the May contract last week.

"The cash market for trading crude oil on the Gulf has weakened significantly," said Andrew Lipow, president of Houston-based consultancy Lipow Oil Associates.

Reformulated gasoline blendstock, or RBOB, for May delivery fell 3.48 cents, or 1.1%, to $3.0403 a gallon, the lowest since April 11. May diesel fell 3.47 cents, or 1.2%, to $2.9519 a gallon, the lowest settlement since April 14.