Safety of An Post saving Bonds/certs

Hi All,
I have a lump sum I would like to invest for a few years.
I am thinking about 'An post' saving bonds (3 years) and Saving certs (5.5 years) as thay have the best rate at present and are government gaurenteed. However, I was wondering what would happen if the country did go belly up and the IMF/EU had to take charge...

Worst case senario - is there a risk that I could lose my investment ? Or would the EU stand over investments in Irish government Bonds if the country did go bankcrupt............
would like to know your thought.

If investments in An Post vehicles became worthless, then it's armageddon: things so bad that we can just abandon all hope.

If An Post goes burst the EU will stand over the Irish government bonds...... they can't afford to do nothing as the stability of the county would be at stake.