March 21 (Reuters) - The U.S. Treasury on Friday lifted

economic sanctions against Tornado Cash, a firm that makes

cryptocurrency transactions harder to track, which the Biden

administration had accused of helping launder more than $7

billion for North Korean and other cyber hackers.

The Treasury Department's Office of Foreign Assets

Control blacklisted Tornado Cash in 2022 after concluding it was

helping launder the proceeds of cyber crimes, including more

than $455 million stolen by Lazarus, a North Korean

government-backed hacking group.

Six users of Tornado Cash - a cryptocurrency "mixer" that

obscures the origins and recipients of transactions - had filed

a lawsuit to challenge the sanctions with the financial backing

of the Coinbase crypto exchange.

In November, a U.S. appeals court

found that OFAC had overstepped its authority

, but the sanctions remained in place.

In a statement, the Treasury said it had decided to

repeal them after reviewing legal and policy issues raised by

the use of sanctions within "evolving technology and legal

environments".

Still, the Treasury Department said it remained

concerned about North Korea's "state-sponsored hacking and money

laundering campaign," through which it has stolen digital assets

to finance government activities.

"Securing the digital asset industry from abuse by North

Korea and other illicit actors is essential to establishing U.S.

leadership and ensuring that the American people can benefit

from financial innovation and inclusion," said Treasury

Secretary Scott Bessent.

President Donald Trump has sought to broadly overhaul

U.S. cryptocurrency policies and this month signed an executive

order to

establish a strategic reserve

of cryptocurrencies. He also

held a summit

for industry leaders at the White House.

Two of the co-founders of Tornado Cash

were charged in 2023

with facilitating more than $1 billion in money laundering,

including for the Lazarus Group. One, Roman Storm, awaits trial

and has denied engaging in criminal activity.

Last May, one of Tornado Cash's developers, Alexey

Pertsev, was sentenced to five years and four months in prison

in the Netherlands for money laundering.