The US Justice Department will file a lawsuit on Friday challenging a Georgia election law that imposes new limits on voting, saying that it infringes on the rights of black voters, Attorney General Merrick Garland said.
The Georgia law, which also bans the distribution of water or food to people waiting in long queues at polling places, is one of a wave of new measures passed by Republican-controlled state legislatures this year, fuelled by former president Donald Trump's baseless claims that his November election defeat was the result of widespread fraud.
"This lawsuit is the first of many steps we are taking to ensure that all eligible voters can cast a vote," Mr Garland said.
"We are scrutinising new laws that seek to curb voter access and when we see violations of federal law, we will act."
The lawsuit is the first of many actions the department plans to protect Americans' right to vote, he said.
It will also be offering new guidance on post-election audits, following a wave of challenges to the results of the 2020 supporters by Trump supporters, and issue the Federal Bureau of Investigation and federal prosecutors new directions to prosecute threats to election workers.
“The complaint alleges that the state enacted those restrictions with the purpose of denying or abridging the right to vote on the basis of race of colour,” Mr Garland said.
After a sweeping Democratic-sponsored bill aimed at protecting access to the ballot died on a party-line vote in the Senate this week, President Joe Biden vowed to take other steps to protect voting rights.
The Republican governors of Arizona, Florida and Iowa have also signed new voting restrictions this year, while state legislatures in Pennsylvania and Texas are trying to advance similar measures.
The Georgia law, signed by Governor Brian Kemp on March 25, tightened absentee ballot identification requirements, restricted ballot drop-box use and allowed a Republican-controlled state agency to take over local voting operations. The state was a key battleground in the 2020 presidential election.
Mr Biden, who became the first Democratic presidential candidate in three decades to win Georgia, has staunchly criticised Georgia's new law, calling it an "atrocity".