HONG KONG (Reuters) -Chinese e-retailer Temu said on Wednesday it has been the target of rival Shein's "unlawful exclusionary tactics" since Temu's U.S. launch in 2022, ramping up a feud between the fast-fashion competitors days after a lawsuit was filed.

Temu, owned by PDD Holdings, filed a lawsuit accusing Shein of violating U.S. antitrust laws on Friday. In a statement sent to Reuters on Wednesday, the company said it had to take legal measures to defend its and its merchants' rights due to "escalating attacks" from Shein.

This marks the latest development in the increasingly competitive global fast-fashion market where the Chinese companies are vying for dominance.

Temu's lawsuit on Friday alleges that Shein, which entered the U.S. market in 2017 and has a $66 billion valuation, has abused its market power in trying to coerce manufacturers to shun Temu.

Temu's complaint alleged Shein "forces manufacturers to sign loyalty oaths certifying that they will not do business with Temu."

A Shein spokesperson on Wednesday repeated its initial statement regarding the lawsuit. "We believe this lawsuit is without merit and we will vigorously defend ourselves," the spokesperson said.

(Reporting by Josh Ye; Editing by Jacqueline Wong and Jamie Freed)