You have two options:
1. You can release equity on your home in Ireland and use the funds released to purchase abroad. Most lenders here don't have any issue with this.
2. You can mortgage the foreign property in the country where you are purchasing. Generally, the leding criteria is similar to Ireland but you can expect to pay higher interest rates, typically around 2% higher and you have to fund a deposit as the loan to value ratios are around 75%. Its also likely that you will ahve to pay a fee for having your mortgage arranged.
Personally, I think that the first option is probably the best.