Online marketplace eBay is suing rival Amazon amid claims that the etail goliath poached its third-party sellers.

The lawsuit, lodged in the US, alleges that Amazon representatives signed up for eBay accounts, then used the company’s internal messaging system to persuade users to sell their goods on Amazon instead.

According to eBay, the move violates its user agreement.

In the legal complaint, eBay describes Amazon’s move as an “orchestrated, co-ordinated, worldwide campaign” to “illegally lure eBay sellers”.

Amazon representatives asked eBay sellers to talk on the phone to avoid detection, eBay has alleged in the writ.

It comes less than a month after eBay first made its complaint public, after claiming to have uncovered “an unlawful and troubling scheme on the part of Amazon to solicit eBay sellers to move to Amazon’s platform”.

eBay is now calling for Amazon to stop misusing its messaging platform and to hand over an unspecified sum in compensation.

Amazon said at the time that it was conducting an investigation, but has declined to comment on the lawsuit.

Both Amazon and eBay rely on independent third-party sellers to boost their top-line sales.

More than half of the items sold on Amazon came from third-party sellers in 2017 – the first time in Amazon’s history that the 50% threshold has been breached.