The smiles and the handshakes at the Palestinian-Israeli summit were barely over before Hamas delivered its bleak verdict.
Peace hopes have been revived by the summit
The most powerful of the armed groups in the Palestinian uprising declared that the grand gathering on the Red Sea had changed nothing.
The Israeli Prime Minister, Ariel Sharon, and the Palestinian leader, Mahmoud Abbas, may have announced a truce - but Hamas said that it was not bound by it.
The group said it should have been consulted first.
Hamas said it would not decide on its attitude to the ceasefire until Mr Abbas had given it a first-hand account of the agreement reached with Israel.
Another militant group, Islamic Jihad, adopted the same position.
Weary of violence
Hamas' statement may have taken some of the warmth out of the post-summit glow.
But in reality it is unlikely to make much difference to the situation on the ground - at least in the short term.
Hamas and Islamic Jihad have been broadly observing an unofficial ceasefire for nearly three weeks.
They reached an understanding with Mr Abbas that they would rein themselves in - allowing him to begin negotiations with the Israelis against a background of calm.
Nothing in the post-summit statements by either group suggests that they might go back on the offensive now.
Most Palestinians are desperate to see an end to violence
The great majority of Palestinians are desperately weary of the years of violence and the economic collapse that they have brought.
Mr Abbas says he wants to end the Israeli occupation by means of negotiation - and there is a widespread desire here to see him given the chance to try.
In Gaza, you often hear too that the armed factions are themselves tired and that an easing of the Israeli army's pressure - for a time at least - would be welcome.
On top of this there is the hope and expectation that the international community is beginning to attach to the prospect of a revival of the peace process.
'Manoeuvring for concessions'
Hamas is pragmatic and politically sophisticated.
It knows that this is a time for restraint. It would not be clever to rock the boat badly now.
And Mr Abbas would have been most unlikely to have given his sweeping commitment at the summit to end the violence if he thought there was a real risk that the likes of Hamas might go on the attack soon.
The world community is watching where Palestinians will turn
By holding back and refusing to commit to the formal ceasefire, Hamas has bought itself time to judge Israel by its actions.
If, for example, the release of Palestinian prisoners is not extensive enough, Hamas may say that the Israelis are not paying a high enough price to draw it into the officially declared truce.
Observers here also believe that by refusing to go along with Mr Abbas's formally declared ceasefire, Hamas is playing for advantage in the Palestinian political arena.
"Hamas is manoeuvring," says the Gaza-based analyst, Sallah Abdelshafi.
"Its tactic is to see how much it can extract from Mahmoud Abbas in terms of internal concessions."
If Mr Abbas tries to coax Hamas into acknowledging the official truce, the group may well seek commitments on a range of issues.
For example it might demand assurances that its militants will not be disarmed, or that election laws are not drawn up in a way that discriminates against it.