The US justice department has said it will sue Georgia over its new law limiting ballot access, in the Biden administration’s first big legal action against voting restrictions in Republican-led states.

Merrick Garland, the attorney-general, announced the move on Friday and signalled it could be a precursor to action against other states that have adopted or were considering similar measures to limit voting.

“Our complaint alleges that recent changes to Georgia’s election laws were enacted with the purpose of denying or abridging the right of black Georgians to vote on account of their race or colour,” Garland said.

The battle over voting right is shaping up to become one of the most contentious political fights of the post-Trump era, with Democrats and Republicans engaged in fierce state-level fights aimed at shaping the landscape for the 2022 midterm elections.

Democrats have accused Republicans of using new voting restraints to disenfranchise black and other traditionally Democratic voters, while Republicans have countered that loose eligibility rules have allowed rampant fraud — an unsubstantiated allegation often repeated by former President Donald Trump.

The Biden administration and congressional Democrats suffered a setback in their efforts to advance legislation to protect voting rights nationwide when Senate Republicans blocked a bill this week that would have prevented states from enacting laws that would restrict voting.

As well as becoming a big political flashpoint, Republican efforts to curb voting access have also created a rift with business, with some large US companies publicly opposing the push in Georgia and several other states.

Justice department officials said their case focused mainly on provisions in the Georgia law that reduced access to absentee voting. Kristen Clarke, the assistant attorney-general for civil rights, said the measures were “pushing more black voters to in-person voting, where they will be more likely than white voters to confront long lines”.

Garland had vowed from his first days leading the justice department to beef up enforcement of voting protections. He insisted on Friday that any violations of existing federal voting laws — including the 1965 Voting Rights Act — would be challenged.

The DoJ would “analyse other state laws that have been passed, and we are following the progress of legislative proposals under consideration in additional states where we believe the civil rights of Americans have been violated. We will not hesitate to act,” Garland said.

The legal fight over voting rights is likely to be shaped by a forthcoming Supreme Court ruling on the issue, which is expected before the end of June. The political battle is also expected to rage on over the coming months and into the 2022 midterm elections.

Earlier this month in Tulsa, Oklahoma, Biden vowed to “fight like heck” to protect voting rights despite the obstacles on Capitol Hill, as he commemorated the 100-year anniversary of a deadly and destructive assault on a thriving black neighbourhood by a white mob.

He also put Kamala Harris, the vice-president, in charge of his administration’s voting rights portfolio.

According to the Brennan Center for Justice, a think-tank, at least 17 states have enacted 28 new laws restricting voting access since the start of the year. Besides Georgia, other such states include Florida, Arizona, Indiana and Iowa. Texas almost approved its own curbs to voting access, but the effort was scuppered, at least temporarily, at the last minute after Democrats staged a dramatic walkout from the state legislature.