American tourism to Ireland is holding up despite a collapse in the overall numbers of people visiting the Emerald Isle.

The latest shock figures from the Central Statistics Office show that the numbers of overseas visitors are down by some 23 percent.

The CSO says that Ireland lost a whopping 100,000 visitors each month in 2010.

However, there was a much smaller drop in visitors from North America, with the numbers down by just 3 percent on 2009 figures.

Overall, 1.084 million people visited Ireland so far in 2010, down by some 317,000 people on the same time last year.

The downward trend was sharpest during the St Patrick's Day season.

The numbers arriving in Ireland during March fell by over 3,500 each day to a total of 434,200. In contrast, 634,200 people visited Ireland in March 2008.

Irish Tourism Minister Mary Hanafin said the main factor was the steep exchange rate between Ireland its closest neighbor Britain.

The CSO says 200,000 fewer British visitors came to Ireland in the first quarter of the year than in 2009, a drop of 27 percent, as against 122,000, or 25 percent, fewer European visitors.

"While the level of decrease is worrying, I understand that outbound travel from Britain to all euro zone destinations was also down in the first months of the year," Hanafin said.

Interestingly, Hanafin said visitors from long-haul destinations (apart from the U.S. and Canada) increased by 11 percent in the first three months of 2010.

Fine Gael tourism spokesperson Olivia Mitchell said that March was "supposed to herald an upswing in the number of tourists coming here, with the St Patrick's Festival forming the centerpiece of the month", but the reverse had happened.

Tourism Ireland also pointed to the difficulties created by the volcanic ash crisis but said there was still time to make Ireland a must-visit destination.

Tourism Ireland chief executive Niall Gibbons said that with over 60 percent of foreign holidaymakers coming between May and September, "there is still everything to play for."