President George W Bush has approved what would be the first execution by the US military since 1961, though court appeals are likely to continue delaying the 20-year-old case indefinitely, the White House said late Monday.

A Bush spokeswoman issued a statement saying that Bush had given the go ahead for a sentence of capital punishment to be carried out against Private Ronald Gray, who was convicted by a military court in 1988 at Fort Bragg, North Carolina, of the rapes and murders of two women, one a fellow soldier and the other a cab driver, and the attempted murder of a second servicewoman.

In a state civilian court, he was convicted of two other murders and further rapes during the same 1986-87 crime spree.

It remains unclear what method of execution would be used by the military, which has at least five other convicts on death row.