Chrispitt, even though you are in another country what is likely to happen if your phone line is cut is that your monitoring company cannot monitor the alarm.
This obviously causes a problem, so what you need to do is contact your monitoring co and ask them the question - not an internet forum where we do not know what your contract with them says.
Give them an alternative number/mobile etc to contact if the line fails so they can check if everything is OK.
IF your phone line is accessible outside your property you might want to take steps to make it so it cannot easily be cut I.e cover it.