The Supreme Court in the Philippines has overturned the conviction of Imelda Marcos on corruption charges, for which she had earlier been sentenced to at least nine years in jail.

Mrs Marcos was not in court for the hearing and there was no immediate comment from her.

The authorities have been trying to send her to prison since her husband, President Ferdinand Marcos, was overthrown by a popular revolt 12 years ago, and this was the closest they had come so far.

In January the Supreme Court had upheld the verdict of a lower court which had found Mrs Marcos guilty of corruption and sentenced her to between nine and 12 years in prison.

But Mrs Marcos had one last chance to appeal and the result is that the Supreme Court has reversed its earlier decision and there is now no longer any imminent threat of Mrs Marcos being locked up.

Mrs Marcos still faces dozens of other criminal cases, but the fact that years of efforts have failed to secure a conviction show how difficult it is for the authorities here to prove their main contention - that Mrs Marcos, along with President Marcos, embezzled millions upon millions of dollars' worth of assets during his 20 years in power.

Mrs Marcos has always said that she and her late husband, who died in exile, are innocent. Indeed, it may in the end be impossible ever to prove that Mrs Marcos was a criminal.