Channel Nine has officially retained the rights to broadcast international cricket in Australia for the next five years.

In the richest television agreement in the game's history, Nine will pay in the region of $450 million in cash and contra advertising to televise home international matches between November and February. Nine trumped Network Ten by exercising its last-rights privilege from its previous contract with Cricket Australia.

Nine management signed the documentation for the deal in Sydney at 4.10pm on Monday afternoon, 50 minutes before the deadline, formally clinching the sought-after broadcast rights.

"Nine Entertainment is today a larger, stronger and more profitable company than it was yesterday," Nine chief executive David Gyngell said.

Staff at the network were earlier on Monday that the network had kept the coverage of the cricket. The new deal will be formally announced by CA in Melbourne on Tuesday afternoon.