President Donald Trump began a solemn Memorial Day railing against North Carolina Gov. Roy Cooper, a Democrat, ahead of the 2020 Republican National Convention, threatening to pull it out of Charlotte, where the convention is expected to be held August 24 to 27.

“I love the Great State of North Carolina, so much so that I insisted on having the Republican National Convention in Charlotte at the end of August,” Trump said in a series of tweets.

“We all want to be in Charlotte, we love North Carolina, but having a sense now is absolutely essential because of the rules and regulations that are involved, and we look forward to working with Gov. Cooper, getting a swift response, and, if need be, moving the national convention to a state that is farther along on reopening and can say with confidence that we can gather there,” he said.

The Republican convention, which is scheduled to be held in the same uptown arena where President Barack Obama accepted his nomination to a second term in 2012, is awash in uncertainty as party officials determine how to navigate a presidential campaign during a public health crisis.

A spokeswoman for the governor, Dory MacMillan, said in a statement on Monday that state officials were working with the Republican National Committee “and will review its plans as they make decisions about how to hold the convention in Charlotte.”