The Irish Travel Agents Association is reminding all Irish passport holders they'll need a valid electronic passport if they want to visit America.

New rules, requiring all Irish people who are able to travel to the US via the Visa Waiver Program to have an electronic passport come into effect today.

Although anyone who doesn't have a valid electronic passport is still eligible to travel, however, they will need to have a valid non-immigrant visa issued by a US embassy or consulate.

ITAA CEO Pat Dawson is urging all people travelling to the US to check their passport before: "I believe from the Department of Foreign Affairs, there are 171,000 that fall into that gap, and those travelling in the next week or two should contact the U.S. embassy in order to go along to get their Visa allocated."