Some House Republicans want to make disaster aid contingent upon finding offsetting cuts elsewhere:

While much of Joplin, Mo., is still under rubble from a devastating tornado, conservatives inCongress are starting to argue for a tougher approach to disaster aid, demanding that any funding be offset by cutting federal money elsewhere.
Disasters will no longer be considered “emergencies” if conservatives win this battle to redefine the way Congress funds aid packages for states and cities stricken by natural and man-made catastrophes.

The problem, of course, is that spending exists because it either serves a necessary purpose, has a powerful constituency, or both. When you attempt to cut spending, you therefore create political opposition. Tying anything to spending cuts makes it harder to accomplish. The Simpsons made this point quite succinctly some years ago:

KENT BROCKMAN: With our utter annihilation imminent, our federal government has snapped into action. We go live now via satellite to the floor of the United States congress.
SPEAKER: Then it is unanimous, we are going to approve the bill to evacuate the town of Springfield in the great state of--
CONGRESSMAN: Wait a second, I want to tack on a rider to that bill - $30 million of taxpayer money to support the perverted arts.
SPEAKER: All in favor of the amended Springfield-slash-pervert bill?
SPEAKER: Bill defeated.
KENT BROCKMAN: I've said it before and I'll say it again: democracy simply doesn't work.

Now, the principle that disaster spending ought to be accounted for in the budget is perfectly sound. Congress could establish a regular found appropriating the average annual spending on disasters, on the assumption that it would spend less than that amount in the typical year, and could spend greater sums in the case of true disasters. (It could always go over the limit in the case of something gargantuan.) But making disaster spending contingent on securing other spending cuts is a crazy bad idea, one that anybody actually faced with the effects of a disaster would never endorse.