The Corcyrians were livid when they became aware of the Corinthian involvement and immediately laid siege to Epidamnus. Later, when they heard of Corinthian preparations for war, the Corcyrians sent an embassy to Corinth to negotiate a settlement. Their offers were ignored by Corinth who sent an armada to Epidamnus to break the siege. At the resulting battle of Leucimme, the Corinthians were defeated.
Stung by defeat, the Corinthians spent the next year building ships to prepare for a decisive battle. Corcyra, for its part, appealed to Athens seeking arbitration. Both parties gave presentations to the Athenians in 433, who eventually sided with Corcyra and executed a treaty of protection in case Corcyra was attacked. Athens had walked a fine line between protecting Corcyra and breaking the Peloponnesean Treaty.