Seaspan Corp has ripped up $520m in contracts to build four container ships and has warned that a legal claim may follow.

The container ship owner, a subsidiary of US-listed Atlas Corp, said the cancellation involves four 7,700-teu, dual-fuel newbuildings.

Seaspan did not explain the reason for tearing up the contracts, other than to say that the counterparty failed to live up to some terms of the deal.