The new Western Sydney Stadium is unlikely to be open for the first month of the 2019 NRL season as discussions begin about a potential Easter Monday launch between the Parramatta Eels and the Wests Tigers.

Construction of the $300 million 30,000-seat venue, which will have the steepest grandstands in the country, is set to be completed by April next year.

Easter Monday falls on April 22 in 2019, with discussions already underway about opening the venue with two western Sydney giants on a public holiday.

The Eels' original plan to play the first match against the St George Illawarra Dragons, like they did more than three decades ago when Parramatta Stadium was built, isn't dead in the water.

However, the club is working on an alternative option should the opening of the stadium fall around the same time as the traditional Eels-Tigers Easter Monday clash.

The NRL had hoped the stadium would be ready in February to launch the venue with a weekend Nines tournament, however attention has turned to a potential 2020 tournament in Western Sydney with Brisbane in the box seat for next year.

Easter Monday launch of new Parramatta Stadium?

It's understood the Wests Tigers, who have a long-term deal in place with ANZ Stadium, are also in discussions about transferring some matches from Sydney Olympic Park to Western Sydney Stadium next year.

They have a long-term deal in place to play at least four matches a year at ANZ Stadium, but given VenuesLive now operate both the Olympic Park venue and the new Parramatta stadium, terms of the deal could be up for negotiation.

The Tigers are yet to commit to their suburban grounds but it's expected they will continue to play at least three matches out of Campbelltown and Leichhardt, especially with murmurs gathering momentum that suburban grounds could receive a financial injection as part of the government's stadiums strategy.

South Sydney, Canterbury and St George Illawarra are also weighing up the possibility of using the new Western Sydney facility in some capacity.

It's likely the Rabbitohs and Bulldogs, who have met with the state government and opposition leader Luke Foley, will continue their current arrangement with ANZ Stadium next year.

However, they are waiting on the government to provide clarity in regards to constructing timing of the Olympic stadium before determining if or how many games they will play in Parramatta from 2020 while ANZ Stadium is being renovated.

The Sydney Roosters have knocked back an expression of interest to take some games to western Sydney and will play nine or 10 of their home matches at the Sydney Cricket Ground next year while Allianz Stadium is being knocked down and rebuilt.

The Panthers have shown no interest in playing matches out of Parramatta.