The English star told Dragons officials of his desire to return home and play in the Super League while he is still at the top of his game and due to homesickness, despite still having three years to run on his contract.
The 30-year old, who is recovering from shoulder surgery, is expected to be released from his deal at the end of next season and move to England for the 2020 campaign.
The decision reportedly caught Dragons officials off guard and has thrown off the club’s pre-season preparation and put a void in their playmaking position.
It is understood that several Super League clubs are watching the situation with interest, including Huddersfield.
Widdop has made 185 NRL appearances for the Red V and Melbourne Storm after making his debut in the league in 20210, but has previously stated while representing England that it would be a “fairy tale to end my career here”.