Toyota Motor Corp., facing capacity constraints in North America, may boost exports from Japan for the first time in three years to meet its global sales target.

Weak sales in resource-rich and emerging countries have made it "very difficult" to meet the 2015 target, Managing Officer Yoichi Miyazaki said last month, according to a newsletter by the company's labor union.

Toyota must make up for the shortfall by boosting sales in developed markets, he said, asking for the cooperation of the company's Japanese workers in handling the increased workload.