"A Rugby World Cup in Ireland would prove to be a hugely attractive destination for rugby supporters from throughout the world and we would relish the opportunity to welcome them to one of the world's major sports gatherings, the Rugby World Cup, in 2023," he said.
"I am confident, with the co-operation already in evidence between both governments, sporting bodies and the general public, Ireland would deliver a hugely successful tournament for World Rugby."
Last week the Northern Ireland Assembly was told that delays around work at Casement Park were creating a bad impression for bid organisers.
Plans have been effectively stalled since the High Court overturned a decision to approve a 38,000-capacity stadium in 2014.
The judge found that Environment Minister Mark H Durkan acted unlawfully in granting permission a year earlier following a legal challenge by residents living close to the stadium.
However, Sports Minister Caral Ni Chuilin has repeatedly insisted that a new stadium will be built.
She said: "A redeveloped Casement Park is a Programme for Government commitment and integral to the bid for 2023.
"I remain committed to ensuring that we deliver on that commitment and I am confident we will do so."
- Daily Mail