The Philippines has apologized to Taiwan for the shooting death of a Taiwanese fisherman by the coast guard - an incident that has added to an already tense relationship.

The Philippines' top representative in Taipei voiced his government's deep regret to Taiwanese Foreign Minister David Lin Wednesday. Another Philippines official plans to meet with the family of the fisherman.

Both countries plan a thorough investigation.

Taiwan threatened to begin naval exercises near the Philippines Thursday if it did not get what it considers to be a satisfactory apology. It is unclear of those exercises will still go on.

A Philippine Coast Guard ship opened fire on the fishing boat last Thursday in the South China Sea where both countries' economic interests overlap. A 65-year-old fisherman was killed.

Taiwan and the Philippines, along with Brunei, China, Malaysia, and Vietnam all have competing claims to parts of the sea, which may be rich in oil and natural gas.