Minister for Transport, Tourism and Sport Shane Ross had almost double the number of diners in the Oireachtas Members' Restaurant than the rest of his Cabinet colleagues combined.

Mr Ross invited more than 500 guests to dine in the restaurant during the first six months of this year.

The figures were released to RTÉ News under Freedom of Information legislation.

There are several eateries within the Houses of the Oireachtas, including a self-service canteen, the Dáil bar and a small grab-and-go tea and coffee area in the newer annex, LH 2000.

The most salubrious venue is the private members' dining room, which is reserved solely for TDs, ministers and their guests.

Without an invitation, there is no reservation.

Community groups, residents' associations, party branch members and groups relating to the work of ministerial departments usually make up those who dine in the restaurant.

It is a place to impress.

Equally impressive is the number of guests brought into the restaurant by one Cabinet minister in the first six months of this year.

The figures show Minister Ross had just over five times more visitors than the next biggest invitee, his Dublin-Rathdown constituency colleague, Minister for Culture, Heritage and the Gaeltacht Josepha Madigan.

Between January and June, Minister Ross invited 507 guests to the Members' Restaurant compared to Minister Madigan's 95 guests.

Minister for Business, Enterprise and Innovation Heather Humphreys and Minister for Children and Youth Affairs Katherine Zappone invited 56 and 42 guests, respectively.

Minister for Justice Charlie Flanagan had 20 guests, Minister for Housing Eoghan Murphy had 16, while Minister for Health Simon Harris had 14 recorded guests.

Taoiseach Leo Varadkar had eight guests, Tánaiste and Minister for Foreign Affairs Simon Coveney and Minister for Communications and Climate Action Richard Bruton both had six.

Minister for Agriculture Michael Creed had four guests in the restaurant, while Minister for Social Affairs Regina Doherty had three.

Minister for Finance Paschal Donohoe, Minister Michael Ring of Rural Affairs and Minister for Education Joe McHugh are listed as having no invited guests during this time.

2019 Dáil Restaurant Member's Guests

1 January 2019 to 6 June 2019

Shane Ross 507

Josepha Madigan 95

Heather Humphreys 56

Katherine Zappone 42

Charlie Flanagan 20

Eoghan Murphy 16

Simon Harris 14

Leo Varadkar 8

Simon Coveney 6

Richard Bruton 6

Michael Creed 4

Regina Doherty 3

Paschal Donohoe 0

Michael Ring 0

Joe McHugh 0

While the figures indicate the level of use of the restaurant by Cabinet members, they do not necessarily reflect the true numbers going through the main dining room.

Bookings for the Members' Restaurant are usually made centrally through the Oireachtas Catering Administration Office.

Members are advised to book in advance when large groups are expected.

However, as pointed out by the Houses of the Oireachtas, individual or smaller group bookings may be accommodated on "an ad hoc basis", provided there is enough capacity on the day, but the number of guests may not be recorded.

Also, where a booking is made in the name of a member, it does not necessarily mean that all of the number of guests booked, attended on the day.

Bookings for guests may be made in the name of a staff member so they may not be identified as those of a minister.

Some Oireachtas members choose to go in with guests on spec and pay themselves.

When asked about the number of guests, Minister Ross said he "regularly hosts voluntary groups from civic society on visits to Leinster House", typically including "a full tour of both the Dáil and Seanad and, sometimes, a meal".

"Bodies such as the Irish Road Victims' Association, the Men's Sheds, school children, disability groups and active retirement members have benefited. Volunteers from sports clubs, heritage societies and others have also taken the opportunity to see Leinster House at work."

In a statement, he added: "I frequently offer a tour of the House, plus lunch or dinner for four, as raffle prizes to charities holding table quizzes or seeking to raise funds for schools, hospitals, community projects or other good causes.

"This year, over a third of the Leinster House restaurant events came into this category."

Minister Ross said all the bills were paid by him personally.