The benchmark Nikkei 225 index gained 0.04 percent or 8.12 points to 20,487.54 in the first few minutes while the broader Topix index was up 0.06 percent or 0.86 points at 1,491.21.

Wall Street staged a late rally on Wednesday as the gloom lifted on a plunge in crude oil inventories, pointing to sustained demand for fuel, a sign of economic health.

But investors remained worried about the US-China trade war and Britain's exit from the European Union.

"Japanese stock prices will likely move narrowly... with no sign of progress in the US-China trade negotiations," Okasan Online Securities said in a note.

Investor fears of a no-deal Brexit have also increased as Britain's government moved to extend the suspension of parliament.

The pound remained weak Thursday, buying $1.2214 against $1.2213 in New York Wednesday afternoon.

The dollar was trading at 106.03 yen against 106.14 yen.

Shares in Suzuki Motor jumped 1.95 percent to 4,165 yen after auto giant Toyota said it would take a nearly five-percent stake in small-car specialist.

Toyota shares were up 0.04 percent at 6,892 yen.

Energy shares rose with oil explorer Inpex rising 0.73 percent to 904.6.