A letter from major industry and public sector groups involved with Shannon told Mr Ahern that liberalisation of transatlantic travel would require a five-year transition period.
Under the current agreement, US airlines wising to fly into Dublin must provide a one-for-one flight in and out of Shannon.
The EU is moving to an Open Skies Policy, doing away with such requirements.
The letter was signed by Shannon Development chairman Liam McElligott; Shannon Airport Authority chairman Pat Shanahan, and Mid-West Regional Authority director Tom Kirby.
It is backed by major industrial, commercial and tourism bodies in the mid-west and west.
The letter says: “it is the considered view of this group that any move to a liberalised transatlantic aviation regime between Ireland and North America will require an adequate transition period and an integrated package of counter initiatives to ensure the continued growth of the economy of the west of Ireland and that Shannon International Airport will remain a key driver of economic development.”
The group told the Taoiseach a western rail corridor with a link to Shannon Airport must be given priority attention.
World-class projects such as the building of an international convention centre and a world trade centre are also called for.
The letter continues: “It is vitally important that the west of Ireland is strongly branded and promoted in North America and other key markets. This will require a dedicated, well-resourced marketing and development fund to enable multi-annual, dynamic promotional campaign to be rolled out.”
The group says that these measures will be necessary if the west is to play a full part in national economic development.