The Standards in Public Office Commission (SIPO) has said it is "disappointed" that a review of lobbying legislation has recommended against amending the law to enhance enforcement powers.
The Second Statutory Review of the Regulation of Lobbying Act 2015, which was published today by the Department of Public Expenditure and Reform, found that overall there was "widespread acceptance of and support for the legislation".
It states that the regulatory system is "generally seen as strong, with compliance the norm".
The review rules out any changes to the legislation, saying that this should only be considered "...where a compelling business case for change is clear and unequivocal".
It says that while some issues have been raised by the review, they do not go to the heart of the operation of the act.
It notes that submissions to the review were mainly concerned with implementation and procedural matters, with a significant focus on a perceived need for more guidance, education and clarity.
However, the Standards in Public Office Commission, which oversees regulation of lobbying, said it was disappointed that none of its 22 recommendations on issues including enforcement were adopted.
It also voiced concern about provisions governing post-employment obligations - whereby certain public officials are required to go through a "cooling-off" period before taking certain posts in the private sector.
SIPO Head of Ethics and Lobbying Regulation Sherry Perrault said it was the commission's view that a range of specific issues could only be addressed by amending the law, rather than just by greater guidance or clarification.
She stated: "This includes, for example, introducing enforcement powers for breaches of the Act's post-employment provisions, as well as requiring public officials to decline further communications with persons who fail to comply with the Act".
Ms Perrault cited the case of an unnamed public official who had breached the rules requiring a cooling off period.
She said that despite notifying the official, the new employer and the Minister for Public Expenditure and Reform, the commission was powerless to take enforcement action over the breach.
The review also reveals that the Irish employers group IBEC has been the most active lobbying body since lobbying was regulated in 2015.
Over 1,950 persons and bodies have registered as lobbyists since the legislation came into effect four years ago.
As of 21 January last, over 40,000 lobbying returns have been made and are available to view on a register.
IBEC accounted for 30% of lobbying activity, with 1,735 notifications to the register.
In second place was the Irish Farmers Association, which registered 1,373 incidents or 24% of lobbying.
Macra na Feirme and the Irish Creamery Milk Suppliers Association each lodged 7% of lobbying notifications.
The Consultative Committee of the Accountancy Bodies of Ireland, Chambers Ireland and Cork Chamber each accounted for 6% of lobbying registrations.
The Irish Congress of Trade Unions and the Construction Industry Federation each represented 5% of lobbying notifications, with the Irish Tax Institute accounting for 4%.
Most lobbying activity was targeted at the Dáil - with 34% of notifications involving that body.
Seanad Éireann accounted for 14%, followed by the Department of Health (9%) and the Department of Finance (8%).
The Department of Agriculture Food and the Marine and the Department of the Taoiseach received 7% each of lobbying approaches, the European Parliament received 6%.
There were 27 submissions to the review process.