Bitcoin dipped 5.16 percent to $33,849.47 at 18:00 GMT on Saturday, losing $1,842.99 from its previous close.
Ether, the coin linked to the ethereum blockchain network, dropped 6.26 percent to $2,262.06 on Saturday, losing $151.11 from its previous close.
Bitcoin, the world's biggest and best-known cryptocurrency, is down 47.8 percent from the year's high of $64,895.22 on April 14.
It has been less volatile in the past week but losses this month have been heavy at 38 percent, driven by growing regulatory pressures on the sector. It is trading at levels last seen in January and at roughly half its peak value.