UPDATED 

President Saleh, who had been receiving treatment in Saudi Arabia since he was badly injured in an assassination attempt last June,arrived in Sanaa suddenly on Friday morning amid celebratory gunfire from his supporters.

The situation in Yemen has deteriorated markedly during the last week and unless the president has some dramatic new move up his sleeve, such as resignation, his return seems almost certain to make matters worse.

The Saudis and Americans had been trying to keep him in Riyadh in the hope that a transition of power could be arranged, but efforts in that direction have made very little progress. 

Earlier this month, John Brennan, President Obama's counter-terrorism adviser (who has been heavily involved in discussions about Yemen) was quoted as saying that he no longer objected to Saleh returning home. 

According to the Yemen Post, Brennan said he "now felt comfortable enough" to allow Saleh's return, though he would not condone such a move either.

"I've told him that I do not believe it's in his interests, Yemen's interests or our interests ... to go back to Yemen," Brennan reportedly said.

On Monday, Saleh was also met the Saudi King. Details of their meeting were not disclosed, though it's said they discussed "ongoing violence in Yemen".

During Saleh's absence, his son and nephews – who hold senior posts in the security forces – have been fighting on his behalf, ranged against Saleh's kinsman, General Ali Muhsen, and the Ahmar family's tribal militia. The result was a military stalemate and, following the recent massacres of protesters on the streets, Saleh presumably argued that his return was necessary in order to restore order. Whether that will be the actual result is another matter.

There were rumours in Sanaa early on Friday that Saleh was preparing to address his party, the General People's Congress, and announce his resignation. How credible those rumours are is difficult to judge at present, and they could simply be a ruse aimed at quietening things down.

If he really intends to step down, he could have done so earlier from Saudi Arabia. By returning to Yemen and then resigning he would expose himself to the risk of prosecution. Before leaving for Saudi he had been seeking guarantees of immunity as part of a transition deal.

A straightforward, clean-cut resignation would be very much out of character; if Saleh does announce that he is stepping down, it would be surprising if there were not a lot of strings and conditions attached.

There are reports that protesters in Sanaa have welcomed news of Saleh's return as providing an opportunity to put him on trial.

Regarding the timing of Saleh's return, it may be worth noting that next Monday – September 26 – is the anniversary of the republican revolution that overthrew North Yemen's king in 1962. It is a national holiday, usually marked by a speech from the president.

Posted by Brian Whitaker, 23 September 2011