"The enemy is still evading the commitments it made to our brothers in Egypt," Mr Al Nakhala said.
"The enemy government must bear full responsibility for that."
Israel said its air strikes launched on August 5 on positions of the Iran-backed Islamic Jihad in Gaza were a "pre-emptive" operation to avert an imminent attack.
In response, Islamic Jihad fired more than 1,000 rockets, but many of them either hit farmland or were intercepted by Israel's air defence system.
In the Gaza Strip, according to the enclave's health ministry, 49 Palestinians were killed, 17 of them children, and more than 350 wounded.
In Israel, shrapnel wounded three people.
Gaza Strip hit by Israeli strikes — in pictures
Islamic Jihad said the truce included an Egyptian commitment to work towards the release of two prisoners — Bassem Al Saadi, a senior figure in the group's political wing, and militant Khalil Awawdeh.
Mr Al Saadi, who was arrested on August 1 in the occupied West Bank, was charged in an Israeli military court of affiliation with the Islamic Jihad, as well as "incitement and aiding contact with enemy elements", the army said on Thursday.
It said Mr Al Saadi received Islamic Jihad funding from Gaza and had called for Palestinian attacks on Israelis.
Residents in Gaza Strip welcome ceasefire between Israel and militants - video
Mr Awawdeh, 40, from the southern West Bank, has been held without charge by Israel since December and been refusing food since March, apart from a few days.
He is being held in custody in an Israeli hospital and is said to be in critical condition.
Israel's Supreme Court on Sunday rejected an appeal to release Mr Awawdeh from custody on the grounds that the army had agreed to freeze his administrative detention while he stayed in hospital.
He has vowed to keep up the protest fast until his detention is revoked.