Are you saying
that Sprint refused to allocate the space you required?

That last sentence is based on an assumption not a known fact.

?? It was a question.

I think the real problem here is that Kazakhstan should have a block of
addresses with a short enough prefix to guarantee routing and these
addresses should have been allocated out of this block.

No. Political geography has little to do with the topology of the
Internet, thus allocating to a country doesn't correspond to
topological addressing. One might argue that a service provider in
Kazakhstan should have a short prefix, but a similar argument can be
made for any service provider.

The obvious solution to this immediate problem is to guarantee routing
for the long prefix until the event in Kazakhstan is over and then to
think hard about what to do about similar cases that are not for short
term events.

Right, except you can *never* guarantee routing -- it is a cooperative
effort among service providers and some service providers may choose
not to cooperate. However, the organization wishing to have the long
prefix routed may pay the routing service provider(s) extra for the
special handling necessary to insure the highest probability of
routability to the sites the organization wants to reach. But this
gets somewhat complicated. I would think an easier solution would be
to simply get a block from the upstream ISP...