Hitachi Ltd., NEC Corp. and Casio Computer Co. are considering integrating their mobile phone businesses to improve profitability in the saturated domestic market, industry sources said Friday.

If realized, the three would have a combined share of more than 20 percent in the Japanese market, drawing close to Sharp Corp., the biggest handset maker in terms of market share in fiscal 2008 at 23 percent.

The move, which could come as early as April, could inspire more consolidation in the industry, analysts say.