Floating exchange rate and cost-push inflation?
I would imagine that a falling exchange rate causes the price of imports to rise as the foreign currency becomes stronger against the local currency.

With high inflation exports become more expensive because foreign buyers have to exchange more of their currency to account for the increase in price. This means they cost more per unit in terms of the foreign currency and consequently become less competitive.

The subsequent fall in demand for exports causes the fall in the exchange rate as the demand for exports and local currency are complementary. A weaker local currency means that one unit of local currency is now worth fewer units of foreign currency.

Thus the result is that imports become more expensive as any given amount of imports now costs more in terms of the local currency. Imagine that the exporting nation, say England, sells teddy bears for £5.00 a piece. If the dollar weakened against the pound from \$1.50 to a pound to \$1.56, then as far as a buyer from the United States is concerned, the price of a teddy bear increases from \$7.5 (i.e. 1.50 * 5.00) to \$7.8 (i.e. 1.56 * 5.00).