Prem Watsa-led Fairfax Financial Holdings has agreed to plough another $500m into US-listed containership giant Seaspan Corp.

The deal takes its total investment in the owner to $1bn.

The cash is being pumped in through the exercise of two tranches of warrants.

Seaspan chairman David Sokol said management was "excited" by the latest development.

He said it would "further bolster Seaspan's strategy to lead consolidation in the fragmented containership sector and capitalise on the most compelling opportunities in the shipping sector and beyond it."