Amazon's Prime Day is losing its luster among a critical group: sellers. Some third-party merchants who previously sold China-made goods during Amazon's premier July shopping event are sitting it out this year or reducing the amount of discounted merchandise they offer.

Several sellers on Amazon.com (AMZN) are planning to skip the e-commerce giant's Prime Day sale in June amid concerns that trade tariffs might hit their margins, Reuters reported. Some sellers sell China-made goods,