DUP leader Arlene Foster has asked social media firms to act over what she called “misinformation” by Sinn Féin regarding plans to update Northern Ireland’s electoral register.
The canvass of households is required by UK law to check voter details.
People who do not return their form on time will be removed from the register.
The UK government has rejected suggestions by Sinn Féin that it would amount to a “mass purge” of voters.
On Tuesday Sinn Féin posted a video on Facebook in which it described the canvass as a “blatant attempt to suppress the voice of citizens” in the next assembly election in 2022.
Deputy First Minister Michelle O’Neill, the Sinn Féin vice-president, said she would be challenging the decision to hold the canvass during the pandemic.
But other Stormont parties have criticised Sinn Féin.
Mrs Foster said Sinn Féin was “creating false statements designed to cause confusion and misunderstanding” and that she had written to Facebook and Twitter asking them to remove the posts or mark them as misleading.
She added that the video was seeking to “erode confidence” in the Electoral Office, which carries out the canvass and runs election processes in Northern Ireland.
BBC News NI has asked Facebook and Twitter for a response.
The Electoral Office has said the canvass is necessary to ensure the register is “accurate and complete”.
Alliance Party leader Naomi Long said framing the canvass as a purge was “inflammatory nonsense”.
The Ulster Unionists’ chief whip Robbie Butler said the claim was a “classic example of fake news”.
“The Ulster Unionist Party has confidence in the Electoral Office and the process,” he added.
“We welcome the updating of the register and have no doubt that the period from July to December will be sufficient to ensure that Northern Ireland can develop a new and updated register which is accurate.”
Sinn Féin has said the Electoral Office needs to “implement new ways to make voting easier” for people in an election in a pandemic situation.
The party wants to meet Northern Ireland Secretary Brandon Lewis to discuss the issue.
The last canvass took place in Northern Ireland in 2013.
More than 60,000 voters were removed from the register ahead of the most recent assembly election in 2017.
That figure included some voters who had been allowed a two-year rollover on the register after the 2013 canvass but were no longer deemed eligible.
The next canvass was scheduled for summer 2020 but was delayed due to the pandemic.
From July, details will be sent to every house and registration will be available online or by paper and the process will end in December.
All households are also expected to receive reminders encouraging them to register to vote.
The next assembly election in Northern Ireland is scheduled for May 2022.
Unlike in Great Britain, Northern Ireland does not have an annual canvass process and Westminster sources said 2021 must be a canvass year.