TOKYO: Tokyo stocks opened higher Monday on positive sentiment over a US Covid-19 relief bill, but investors remained cautious after Japan detected cases of the new strain of the virus.

The benchmark Nikkei 225 index rose 0.31 percent, or 82.16 points, to 26,738.77 in early trade, while the broader Topix index was up 0.37 percent, or 6.61 points, at 1,785.02.

"Investors bought back shares, welcoming Trump's tweets on the Covid relief bill," said Toshikazu Horiuchi, a broker at IwaiCosmo Securities.

US President Donald Trump on Sunday signed the massive bill he had previously refused to approve after tweeting that he had "good news" to come.

"But players remained cautious about the impact of rising coronavirus infections, including the country's first cases of the new strain, on the Japanese economy," Horiuchi told AFP.

Japan said Saturday it would halt all new non-resident foreign arrivals from overseas from Monday until late January, strengthening its current border restrictions.

Just before the opening bell on Monday, the government said its industrial production in November was flat compared to the previous month.

"The market largely ignored the figures," Horiuchi said.

The dollar fetched 103.52 yen in early Asian trade, against 103.56 on Friday.

In Tokyo, Mitsubishi Heavy Industries rallied 2.60 percent to 2,977.5 yen following a report that the firm plans to build a massive zero-carbon steel plant running on hydrogen in Austria.

Nintendo jumped 1.05 percent to 65,350 yen and Sony gained 0.46 percent to 9,999 yen as investors bought back shares following recent declines.

But Japan Airlines dropped 2.57 percent to 1,852 yen with its domestic rival ANA Holdings also down 1.99 percent at 2,136.5 yen on concerns over the pandemic.