Hoping to sell house and move to country

We bought a house in late 2005 for 365,000 with a 100% mortgage in what is considered a desirable suburb of Cork city. We currently have approx 340,000 left on this mortgage therefore I think we are in negative equity. Is it possible to cut our losses and take this debt to another property? Or do we have to reduce the LTV to possibly 92% before even considering this? We are hoping to move to the country and build on my fathers land a house of approx 2,400sqft. Any help would be greatly appreciated.

Do you have savings ? If not, you probably should solve this problem first
before consider any move.
In answer to your first question, if you sell this house for less than 340K. the bank will insist that you pay off the debt in full, immediately.

The only way that you might be able to fund your move, is if the site belonged to you, and you were able to mortgage it, to fund the shortfall in the first mortgage.
If you intend getting a mortgage to self build with stage payments, you do need
money to get the building started. Also, you will need to service the mortgage on
the site, and pay rent, while you build.

I have no idea what your income is, any how much of a mortgage you would be
considered for now, but this plan does not seem feasible without savings.

Sorry huskerdu, I should have added that info, first time user. We have savings of 40,000 euros but I presumed I would have needed this as a deposit. We have a combined income of 90,000.