The Environmental Protection Agency (EPA) admits it will be "extremely challenging" to have one million electric vehicles on Irish roads by 2030.
The goal was set out by the Government in its climate action plan and is designed to help reduce harmful emissions.
The EPA says Ireland has not met its 2020 emission reduction targets, but the goal for 2030 can be achieved if current plans are fully implemented.
Stephen Treacy, Senior Scientific Officer with the EPA, says the goal of one million electric cars on Irish roads by the end of the decade is very ambitious "I don't think it's impossible," he said.
"It's certainly extremely challenging, and it will require a big increase in uptake rates over the next number of years, in particular between 2025 and 2030 years as we would expect almost all new vehicles sold to be electric.
"It's certainly a hugely ambitious target and does require the infrastructure to be built out to facilitate their use."
The EPA also reported that restrictions imposed during the Covid-19 pandemic led to a fall in greenhouse gas emissions last year.
However, the watchdog's warning Ireland can't continue to rely on external events to achieve its emissions goals.
According to a new report, Ireland has failed to meet its 2013-2020 EU targets for greenhouse gas emission reductions.
EPA spokesperson, Sharon Finegan, says future targets are still achievable.
"Ireland can meet our current EU commitments over the 2021 to 2030 period. If all current plans and policies are fully implemented," she said.
"They are measures like decarbonisation of the transport fleet. It also is around how we're heating our homes."
Environment minister Eamon Ryan said the country has "to do a hell of a lot more" to tackle greenhouse gas emissions.
"There's an opportunity in each different sector, in agriculture, in transport and in energy to do things better, as well as low carbon actually change the economy for the better," he said.
"That's what we're on track to doing."