London, Sep 28 (IANS) Authorities in the US are forced to put on hold a series of executions because of a shortage of one of the drugs used in lethal injections, a media report said Tuesday.

The lethal injection method is used by 35 states and several of those do not have enough sodium thiopental, an anaesthetic which is used to render condemned prisoners unconscious shortly before their death, the Daily Telegraph reported.

Steve Beshear, the Kentucky governor, has had to postpone signing two death warrants, for killers Ralph Baze and Robert Foley, whose appeals are exhausted.

Oklahoma delayed carrying out a death sentence last month and Arizona is looking for some of the drug ahead of an execution in a month’s time, the report said.

In all there are 17 executions scheduled in nine states before the end of January which require the drug.

Inmates sentenced to death are injected intravenously with three drugs. First they are put to sleep with sodium thiopental, pancuronium bromide then paralyses their muscles and stops their breathing, and finally, potassium chloride stops the heart.

Hospira, a pharmaceutical company which produces the anaesthetic, has blamed the shortage on issues with the supplier of its raw materials, and said new batches of sodium thiopental will not be available until January at the earliest.

Using alternative drugs is not possible for many US states because their execution methods were only established and clearly set out after lengthy court proceedings, the report said.