(ST. LOUIS, AP) — Missouri Gov. Jay Nixon on Friday halted what was to have been the first U.S. execution to use the popular anesthetic propofol, following threats from the European Union to limit the drug’s export if it were used for that purpose.

Nixon also ordered the Missouri Department of Corrections to come up with a different way to perform lethal injections without propofol, the leading anesthetic used in America’s hospitals and clinics. Nearly 90 percent of the nation’s propofol is imported from Europe.

“As governor, my interest is in making sure justice is served and public health is protected,” Nixon said in a statement. “That is why, in light of the issues that have been raised surrounding the use of propofol in executions, I have directed the Department of Corrections that the execution of Allen Nicklasson, as set for October 23, will not proceed.”

Nixon, a Democrat and staunch supporter of the death penalty, did not specifically mention the EU threat in his brief statement. Nixon was Missouri’s longtime attorney general before he was first elected governor in 2008. During his 16 years as attorney general, 59 men were executed.

The leading propofol maker, Germany-based Fresenius Kabi, and anesthesiologists had warned of a possible propofol shortage that could impact millions of Americans if any executions took place.

In a statement, Fresenius Kabi applauded Nixon’s move.

“This is a decision that will be welcomed by the medical community and patients nationwide who were deeply concerned about the potential of a drug shortage,” said John Ducker, CEO of Fresenius Kabi USA. The company said propofol is administered about 50 million times annually in the U.S.

A spokeswoman for the European Union declined comment.

Drug makers in recent years have stopped selling potentially lethal pharmaceuticals to prisons and corrections departments because they don’t want them used in executions. That has left the nearly three dozen death penalty states, including Missouri, scrambling for alternatives.

Missouri altered its execution protocol in April 2012 to use propofol. The drug gained some level of infamy in 2009 when pop star Michael Jackson died of a propofol overdose.

Nixon’s decision also leaves uncertain the execution scheduled for next month for another convicted killer, Joseph Franklin.

Soon after Nixon’s announcement, Missouri Attorney General Chris Koster filed a motion with the Missouri Supreme Court to vacate the Oct. 23 execution date for Nicklasson and to set a new date “soon after” Franklin’s execution date of Nov. 20. A spokeswoman for Koster declined comment.

In addition to concerns raised about how the EU would respond to the execution, Missouri’s decision to use propofol prompted a lawsuit filed on behalf of nearly two dozen death row inmates claiming use of the unproven execution drug could result in pain and suffering for the condemned man.

Koster, a Democrat, and Republican Missouri state Sen. Kurt Schaefer have suggested that if the state can’t execute by lethal injection it consider going back to the gas chamber, something that hasn’t been used since the 1960s. Missouri no longer has a gas chamber but Schaefer recently wrote to Nixon, urging him to consider funding construction of a new one in his next fiscal year budget.

The corrections department on Wednesday agreed to return a shipment of propofol to Louisiana-based distributor Morris & Dickson Co. The company distributes propofol made in Europe by Fresenius Kabi and told the corrections department in November that its shipment was a mistake.

Corrections spokesman David Owen said Wednesday that Missouri had a remaining supply of propofol, all of it domestically made. But Fresenius Kabi spokesman Matt Kuhn said even the use of domestically produced propofol in an execution could prompt the EU to impose export controls.

Meanwhile, Mercer Medical, a Kent, Wash.-based third-party vendor, said Friday in a news release it has asked for the 400 milliliters of propofol it sold to the corrections department in June be returned at the request of the manufacturer, Hospira. The website for Hospira says it is headquartered in Lake Forest, Ill.

Nicklasson was convicted of the 1994 killing of Excelsior Springs businessman Richard Drummond, who stopped to help when a car used by Nicklasson and two others broke down on Interstate 70 in central Missouri. Another man in the car, Dennis Skillicorn, was executed in 2009.

Nicklasson’s attorney, Jennifer Herndon, said she was pleased with the delay, but expects the state to move quickly to revise its execution protocol.

“They’re pretty anxious to execute people so I would think that the state would put something forward sooner rather than later,” Herndon said.

Franklin, a drifter from Alabama, was convicted in the 1977 sniper shooting of Gerald Gordon as a crowd dispersed from a bar mitzvah in suburban St. Louis. Two others were wounded. He has said he tried to start a race war by traveling the country shooting people. When he confessed in 1994 to the shooting, he was serving several life sentences in a federal prison for killing two black joggers in Salt Lake City and an interracial couple in Madison, Wis., and the bombing of a synagogue in Chattanooga, Tenn.