Google has announced it is banning all ads related to the referendum on the Eighth Amendment ahead of the vote on May 25.
It follows a similar move by Facebook, which is rejecting adverts from groups outside the country attempting to influence the referendum.
However, Google seeks to ban all relevant ads in the next few weeks.
The decision will be implemented in the next 24 hours and includes platforms such as Google and YouTube.
It will have no affect on searches performed on Google.
Pro-choice group Together for Yes welcomed the move.
"Together for Yes welcomes the news that Google will ban #8thref ads," they tweeted.
A number of pro-life groups will hold a joint press conference this afternoon at 4pm Google's to respond to Google's announcement.
The move has been widely welcomed, but Fianna Fáil's spokesperson on technology, James Lawless TD, says it has come far too late in the campaign to combat 'fake news'.
"The decision taken by Google today, and that taken by Facebook yesterday, is a positive development but comes far too late in the day," he said.
"This is alarming when you consider a growing number of people solely rely on social media to consume news and shape their decision making process when it comes to elections and referenda."
The Green Party leader Eamon Ryan TD described the move as internationally significant.
"This is not about which side of the referendum you’re on, Yes or No. It is about protecting the integrity of our referendum and political system," he said.
"It is about allowing people to make their own minds up without interference from foreign influence. It is about creating a fair and transparent system, which avoids giving unfair advantage to those with massive online advertising budgets.
"It’s important for how referenda and elections can be protected from undue influence all around the world.
"It’s regrettable that this has been done last minute, in a voluntary capacity by the companies involved.