International Brent crude oil futures LCOc1 were trading down 13 cents at $46.36 per barrel at 0445 GMT, from their last close, Reuters reported.
U.S. West Texas Intermediate (WTI) crude oil futures CLc1 were trading at $45.19 per barrel, down 23 cents, or 0.51 percent, from their last settlement.
A stronger U.S. dollar makes oil, which is priced in dollars, more expensive to buyers in other currencies.
Read alsoReuters: Oil prices fall on U.S. crude stock build, OPEC remains in focus"Oil traded in a sideways range overnight, as stronger U.S. dollar (overshadowed) optimism from Saudi's Energy Minister over a production cut agreement," said Jeffrey Halley, senior market analyst at OANDA brokerage in Singapore.
"With the dollar reigning supreme, Asia trading of crude should have a slightly heavy tone today as traders lighten up positioning into the weekend," Halley said.
The U.S. dollar index .DXY reached a 13-1/2-year high on comments by U.S. Federal Reserve Chair Janet Yellen as she said the rate increase could happen "relatively soon", indicating higher chances of the rate hike in December.
"Commodities were mixed, with the stronger dollar creating headwinds for the sector. Brent crude oil traded around $46 per barrel as investors saw an increasing chance that OPEC would reach an agreement on production cuts," Australian bank ANZ said in a note.
Saudi Arabian Energy Minister Khalid Al-Falih's optimistic comments on potential OPEC cuts came ahead of a meeting of key oil exporters' officials scheduled to take place between 0530 GMT and 0730 GMT on Friday.
The oil exporters' representatives – from Saudi Arabia, Algeria, Russia, Iran, Kuwait, Libya, Venezuela, Bahrain, the United Arab Emirates, Qatar and Nigeria – are meeting in Qatar's capital Doha to discuss details of a potential deal on output cuts.
"I think (OPEC deal) would have a short-term impact on the market...production cap could induce (oil producers) start producing more in the long term if prices go up," said Ric Spooner, a Sydney-based analyst at CMC Markets.
Although Saudi Arabia is leading to reach a deal on cutting outputs, Venezuela President Nicolas Maduro said the OPEC member would finance $2.2 billion from a Chinese credit line to boost oil joint ventures with China National Petroleum Corp CLc1 by around 277,000 barrels per day.
Iran's increasing output also casts doubt on whether an OPEC deal will be able to clear a persistent global oil glut. Iran overtook Saudi Arabia as India's top oil supplier for the first time in October, shipping data showed.
