Dealers meanwhile shrugged off rebounding German business confidence and kept one eye on tense negotiations in Brussels over the European Union budget.
Brent North Sea crude for delivery in January eased 13 cents to $110.42 a barrel in midday trade.
New York's main contract, light sweet crude for January or West Texas Intermediate (WTI), shed 31 cents to $87.07 a barrel.
Crude futures also fell on Thursday owing to the Thankgiving celebrations in the United States, and after the end to a week of cross-border violence between Israel and Palestinian militants that killed at least 160 people.
"Oil prices saw virtually no movement yesterday due to the public holiday in the United States," said Commerzbank analyst Carsten Fritsch.
"Price fluctuations are unlikely to be particularly spectacular today either, as US markets are largely closed for the Thanksgiving weekend."
The oil market see-sawed this week as traders tracked the Middle East unrest and fretted over fiscal concerns in both the eurozone and the United States.
Prices had soared $2 a barrel on Monday, striking one-month highs as violence intensified in the Israel-Gaza conflict, stoking supply worries.
"The ceasefire in the Gaza Strip has eased major oil supply concerns," said Sucden Financial analyst Myrto Sokou.
"However, the political and economic conditions across Middle East remain very tentative, offering mixed signals in the oil market."
Brent oil prices on Monday jumped to $112.20 a barrel -- which was the highest level since October 19. New York crude hit $89.80 a barrel -- last reached on October 22.
The market has also found strong support from hopes that top oil consumer the United States will avoid the so-called "fiscal cliff" of automatic tax increases and spending cuts due in January that risks a return to recession.
A surprise drop in US crude inventories, suggesting stronger energy demand, also lend support to oil futures.
Fresh economic strains in Europe, after Moody's this week downgraded France's sovereign rating, have meanwhile weighed on prices, traders said.