TOKYO, Oct 18 (Reuters) - Japan's Mitsui Life Insurance plans to increase domestic bond holdings in the six months to March while it has no plan to increase foreign bonds, a senior official at the company said on Friday.

The insurer shifted about 30 to 40 billion yen ($306 million to $409 million) of funds to euro bonds from dollar bonds, expecting U.S. bonds to come under pressure after Federal Reserve begins curbing its stimulus, said Sei Sugimoto, executive officer in charge of investment planning at Mitsui Life.