Uncertainty surrounding the 2020 Republican National Convention increased Tuesday as Democratic North Carolina Gov. Roy Cooper rejected the GOP’s request to have a full, in-person convention.

In a letter addressed to the Republican National Committee (RNC), Cooper cited his concerns about the coronavirus pandemic.

“With the nation, the State of North Carolina and the City of Charlotte still under states of emergency it’s important to conduct the RNC convention accordingly. As much as we want the conditions surrounding COVID-19 to be favorable enough for you to hold the convention you describe in late August, it is very unlikely,” Cooper wrote.

“Neither public health officials nor I will risk the health and safety of North Carolinians by providing the guarantee you seek,” Cooper wrote before signing.

The letter is the newest chapter in the back-and-forth between Cooper and the RNC, and his refusal to authorize the convention in the ways that the RNC has envisioned has frustrated many prominent Republicans, including President Donald Trump, who has expressed his frustration with Cooper on Twitter.

GOP party officials have insisted that they still want to hold the convention in North Carolina, but say they have received little guidance from the governor as to how do to it safely.

RNC chairwoman Ronna McDaniel released a statement Tuesday afternoon stating that while North Carolina would likely lose tens of millions of dollars in revenue, the party was obligated to look into hosting its convention in other states whose governors had expressed interest in hosting it, including Florida, Georgia and Tennessee.

GOP leaders are planning on visiting Nashville this week as a potential site as well. “We have an obligation to our delegates and nominee to begin visiting the multiple cities and states who have reached out in recent days about hosting an historic event to show that America is open for business,” McDaniel said.