Romney's hosting contenders and donors next month. REUTERS/Jim Young

Mitt Romney, who earlier this year decided against a third presidential bid after briefly flirting with a run, will jump back into the national political scene next month when he hosts GOP presidential hopefuls and some of the party’s biggest donors in Utah.

Romney’s 2015 E2 Summit will take place June 11-13 in Deer Valley, a ski resort east of Salt Lake City, according to an invitation obtained Thursday by The Washington Post.

Confirmed speakers from the likely 2016 Republican field include Wisconsin Gov. Scott Walker, Sen. Marco Rubio (Fla.), New Jersey Gov. Chris Christie, Ohio Gov. John Kasich, and Sen. Lindsey Graham (S.C.).

Former Florida governor Jeb Bush, long seen as a Romney rival due to tensions between their camps, was invited but will not attend, per a Romney ally.

“The format will be similar to that of the past, with speakers on a range of topics throughout the day and outdoor enthusiast activities each morning and Saturday afternoon,” wrote Spencer Zwick, Romney’s former national finance chairman, in the invitation to Romney’s associates.

Zwick, Romney’s political confidant since the 2012 election, has so far remained uncommitted in the 2016 race. He has frequently expressed hope to Romney’s friends that the former Massachusetts governor will rethink the decision to forgo another campaign, which he announced in late January after weeks of consideration.

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But Romney has resisted the encouragement. After watching Bush collect significant support from the Republican Party’s establishment, he and many of his advisers at the time were unsure of how he would fare.

The summer affair is Romney’s fourth annual summit. The events began as a way for him to personally connect with the power brokers and financiers backing his political operation. The theme of this year’s gathering is the “strength and future of American leadership.”

Other speakers listed are Sen. Kelly Ayotte (R-N.H.), American Enterprise Institute president Arthur Brooks, journalist Katie Couric, former defense secretary Robert Gates, former treasury secretary Lawrence H. Summers, and former Obama adviser David Axelrod, among others.