When the International Committee of the Red Cross announced, as it did at the weekend, that Syria was now in a state of civil war, it seemed to be stating no more than the obvious. For all the efforts of the former UN Secretary-General Kofi Annan, the violence that his mission was intended to quell has not abated. Yesterday, Mr Annan was back in Moscow, trying to persuade Russia that it should sign up to stiffer sanctions and join Western powers in helping to oversee a transition from President Bashar al-Assad's rule.

It would be some consolation to discern here the outlines of an eventual solution, albeit one very far down the line. If Mr Annan judges it worth having further talks in Moscow, then perhaps the Kremlin's position is not as rigid as it seems. And if the ICRC judges that Syria has now descended into all-out civil war, then international rules on the behaviour of the combatants and the protection of civilians might be deemed to apply. There could then be the prospect – remote though it might seem today – of holding Mr Assad and his ministers and his generals to account through the International Criminal Court.

It would probably be more realistic in the short term, however, to see the outlines not of a solution, but of a conflict that is becoming ever more entrenched. While Russia said recently that it would conclude no new arms deals with Syria, it has not altered its public stance on Mr Assad. The Russian foreign minister, Sergei Lavrov, appeared uncompromising before Mr Annan arrived, accusing the West of applying "elements of blackmail". Russia's intransigence may reflect self-interest or pragmatism, or both, but it has been consistent in regarding Mr Assad's fate as the responsibility of Syrians themselves, and regime change without any certainty about what happens next as potentially more destabilising even than the current perils.

Any diplomatic progress in Syria must take that view into account. Not because it is Russia's, but because any plan for a transition has to take into account not just the desirability of ending Mr Assad's rule, but the risk of leaving a vacuum, or a war zone, in the centre of a region that is already highly volatile. Without the broadest international agreement on how to proceed, the risk is not only of continued violence in Syria, but of a proxy regional war.

The truth that should concentrate minds is that time for any ordered, internationally supported transition is running out. Syria may or may not be in a state of all-out civil war – the violence is still concentrated in long-standing centres of resistance – but the disputed areas are expanding , and the violence is becoming more dispersed, even reaching the outskirts of Damascus. Whether the killings at Tremseh last week were committed by militias allied to Mr Assad, as at Houla in May, or resulted from a direct clash between government forces and rebel fighters, they reinforce the reality that Mr Annan's peace efforts have so far failed.

The nub of his plan was that both government and rebel forces should observe a ceasefire; each side has since accused the other of violations. But on the ground, Mr Assad cannot but recognise that fortune is not running in his favour. Any restraint the failed peace plan may have exerted has been accompanied by an increase in the numbers and fire power of the opposition; a trickle of key defections has begun. The best course for Western diplomacy now might be to focus less on persuading Russia to abandon its man in Damascus and more on convincing Mr Assad that the balance of forces in his own country has shifted and his days in power are numbered.