Republican party officials are now actively preparing for the prospect of a contested convention in Cleveland as front-runner Donald Trump continues to draw strong support from the GOP base.

The scenario was discussed by more than 20 leading Republicans Monday at a Washington, DC, dinner held by Republican National Committee Chairman Reince Priebus, the Washington Post reported. A person familiar with who attended the dinner confirmed to Bloomberg that it took place, and that Priebus, members of Congress, establishment lobbyists and others have held similar discussions for weeks.

Should Trump continue to dominate the GOP field in the coming months and amass the required number of delegates to become the official Republican nominee, members of the establishment say they would be forced to contest his nomination on the convention floor in Cleveland from July 18-21.

Trump, who has stirred controversy and drawn support over controversial positions such as rounding up and deporting millions of undocumented workers and enacting a temporary ban on Muslims entering the U.S., is viewed by establishment figures as the surest way for the party to lose the 2016 presidential race, along with major losses in Congress.

While the Republican presidential primary began with Jeb Bush in the lead, no establishment candidate has been able to consolidate enough support to compete with Trump in months.