Bitcoin climbed to the highest since September, briefly surpassing $7 000, as a rally in cryptocurrencies gathered pace in trading over the weekend.
Bitcoin advanced 11% from Friday to $6 957.73 as of 09:01 Tokyo time, having earlier hit $7 585, according to Bitstamp pricing.
The largest cryptocurrency is on a tear after trading closer to $5 000 at the start of May and has more than doubled since mid-December. Still, it remains a long way off its 2017 peak that topped $19 000.
The future of virtual currencies remains a contentious debate amid heat from regulators and news of a hack on one large exchange. New York Attorney General Letitia James last month alleged an $850m cover-up by the companies behind virtual currency Tether and Bitfinex - one of the world's largest crypto exchanges.
Separately, Binance last week said hackers withdrew 7 000 Bitcoins worth about $40m via a single transaction in a "large scale security breach," the latest in a long line of thefts in the digital currency space.