Saudi Arabia has now admitted what the Houthi rebels have long claimed and the Yemeni government has long denied: it is engaged in cross-border military action in Yemen.

The admission, which was possibly accidental, came when Prince Khaled bin Sultan, the deputy defence minister, visited troops in Jizan province earlier today.

"We are not going to stop the bombing until the Houthis retreat tens of kilometers inside their border," the prince said in remarksreported by the Saudi TV channel, al-Arabiya.

Clearly, pursuing the rebels for tens of kilometers beyond the frontier line cannot be achieved without cross-border action.

Al-Arabiya also said that one of the Saudi soldiers earlier reported missing had "returned to the kingdom" on Monday with important maps and other military documents. It did not say from which country he returned but, given the context, the presumption has to be that it was from Yemen.

Four Saudi soldiers are still missing, possibly held captive by the rebels. A Houthi video posted on the internet purports to show one of them receiving medical attention.

Posted by Brian Whitaker, 10 November 2009.