Taoiseach Leo Varadkar has said that abortion services may not be available in every hospital from January but terminations will be accessible in Ireland from the start of 2019.
He said the service has to be "rolled out" and "phased in".
It comes after some GPs warned they will not be ready to start the service in just three weeks and that this could put women who have a termination at risk.
Mr Varadkar insisted he is confident abortion services will be available in Ireland from next month.
He pointed out that the legislation still has to go through the Seanad and may be returned to the Dail for amendments.
He also said it is within the President's prerogative to refer the law to the Supreme Court.
However, he added: "Assuming the legislation is enacted, signed into law by the President, then a service will be available in January.
"Like any new service, it's not going to be a case of just flicking a switch and one day there is no service and the next day it's 100pc available.
"It will have to be rolled out, it will have to be phased in, but we're confident [it] will be available in January.
"It may not be available in every single hospital and every single place, but the service will be available."
Over the weekend, Dr John O'Brien, the president of the Irish College of General Practitioners, cautioned against pushing out the service from January 1.
He said if the proper supports are not finalised by then, "a high quality, patient-centred service is jeopardised and patient care will be compromised".
Separately, the master of the National Maternity Hospital, Dr Rhona Mahony, has also questioned the timeline.
She told RTE Radio that while some services may be available, it would be a "big ask" for the entire service to be rolled out by January.
"At the end of the day, it's very unusual that legislation would be finalised and within days an entire service would be rolled out," Ms Mahony said.
"I'm sure there will be terminations, absolutely, but I still think the service that we would like to see rolled out will not be ready in its entirety by January 1," she added.
The Seanad last night began its consideration of the proposed abortion laws.
There have been claims that some pro-life TDs sought to slow its passage through the Dail by filibustering - a parliamentary delaying tactic involving lengthy speeches.
Senator Ronan Mullen said the process of passing the law is "difficult" and "tragic" for those, like him, who oppose abortion.
However, he pledged not to speak longer than is necessary on the amendments he is proposing and called for both sides to "give each other some space" and avoid "parliamentary obstructive tactics".
Health Minister Simon Harris welcomed his remarks.
"We can vehemently disagree on the content of this legislation, as I know we do, and still have a debate that is respectful and constructive, and, as you rightly say, doesn't filibuster or seek to delay," he said.