US states are facing the prospect of losing further access to the execution drug propofol after the UK's business secretary announced his intent to publish new export controls aimed at banning the export of the drug from the country.

The Guardian reports Business Secretary Vince Cable is set to publish the details of the proposal on Wednesday, 11 June 2012. "We are clear that the state should never be complicit in judiciary executions through the use of British drugs in lethal injections," said cable in a statement to the press.

The export ban on the drug comes just as some states are moving away from sodium thiopental-a barbiturate used to anesthetize patients before a succession of two additional drugs are used to execute a convicted prisoner-in favor of other anesthetizing agents, including propofol and pentobarbital.

New Tactics for Death Penalty Opponents and Proponents

Sodium thiopental has experienced widespread shortages as the result efforts by death penalty opponents, who have been working to disrupt the supply of the drug through import, export and quality regulations. The US Food and Drug Administration (FDA) has even found its authority to exercise enforcement discretion under fire, with a judge ruling in March 2012 that the agency was acting in an "callous" manner in violation of the law.

The strategy may ultimately be backfiring on death penalty opponents as some states are moving to institute single-drug execution methods involving a massive overdose of pentobarbital. The drug is difficult-though possible-to obtain, with all but one drug manufacturer-Oak Pharmaceuticals-choosing to discontinue the drug.

On 10 June, Texas' Department of Criminal Justice announced it would make the switch to pentobarbital after its supply of one of its execution drugs expired. Texas now joins Arizona, Idaho, Ohio and Washington in exclusively using pentobarbital for executions, reports The Associated Press. Other states use propofol, infamously blamed for the death of singing icon Michael Jackson, instead of pentobarbital.

Read more:

The Guardian - UK to ban export of drug approved for use in US executions

AP - Texas switches to 1-drug execution due to shortage

San Antonio Express-News - Official: Texas switches to 1 drug for executions due to shortage of other drug

FDA - Approved Suppliers of Pentobarbital

FDA - Approved Suppliers of Propofol

Read all Regulatory Focus articles on Sodium Thiopental