Tung Oil on Engineered Oak External Door?

[oscis]

Hello All

For reasons I won't embarrass myself with I've ended up with a new Wood engineered (veneered) oak door - Dalston style which appears on most 'Oak' door vendor websites..

I really don't want to varnish or stain it, but I know it'll need to be thoroughly treated. Would a proper treatment of good Tung oil keep it sealed? Or do I need to use something a bit more like wood stain to stop it falling apart?

Thanks!

 

[oscis]

If it helps, the door will be north facing but unprotected from the elements.
Any opinions would be gladly welcomed!