Fine Gael ministers have waved through proposals for reform of the penalty points system - because they believe it will not be completed before a general election.
In a bid to head off a revolt, Transport Minister Shane Ross agreed that graduated speeding fines will not come into effect until a national review of speed limits is published.
A number of rural ministers were prepared to try derail the Independent Alliance minister's plan - but backed down after being briefed on the proposals by Taoiseach Leo Varadkar.
Sources said the Taoiseach's "message" to his colleagues was not to create a fight with Mr Ross over the issue.
The plan got through Cabinet without a major debate. However, Fine Gael ministers do not believe the legislation will be passed before a likely election date next April or May.
A Government spokesperson said: "Time wouldn't necessarily be anybody's friend at the moment."
Mr Ross wants to reduce the punishment for speeders at the lower end of the scale, but dramatically increase the fall-out for the worst offenders.
Drivers caught breaking the speed limit by 20kph to 30kph will get four penalty points and a €100 fine. A new offence of driving more than 30kph above the limit is to be created and will result in a court prosecution and a €2,000 fine.
In all cases conviction for this offence will lead to seven penalty points.
Tanaiste Simon Coveney confirmed to the Herald that the review of speed limits was crucial to convincing Fine Gael colleagues to provisionally back the changes.
"I think the review of the speed limits made a big difference, to be honest, because I think that's what people don't want is people who are caught for speeding unfairly and then punished unfairly," he said.
Mr Ross has also committed to designing an appeals mechanism which will allow "questionable speed limits" to be reconsidered by authorities.
A process will be put in place whereby, if an individual or group believes that a particular speed limit in a location is too high or too low, a technical review which takes account of the Speed Limit Guidelines will be undertaken by a competent assessment panel.
The Government spokesperson said the mechanism does not yet have a name, "so it's really just in its very infancy at the moment".
In a statement Mr Ross indicated he hopes to get the legislation passed by the Dail and Seanad as quickly as possible.
"We don't want to catch people speeding; we want to encourage them to stop speeding so as to prevent deaths and injuries on our roads," he said.
He added that the current ''one penalty fits all' system which means every speeding offence is punished with three points "is not particularly fair".