President Abdel-Fattah El-Sisi said in comments aired on state TV on Saturday that "foreign hands lie behind Friday's attacks" on army soldiers in Sinai that killed 31 troops and injured 30.
Surrounded by top military generals, El-Sisi's comments came immediately following an emergency meeting of the Supreme Council of the Armed Forces (SCAF) on Saturday morning.
At the emergency meeting, which was headed by President Abdel-Fattah El-Sisi, the SCAF tasked a group of its senior leaders with studying the circumstances of the latest terrorist attacks in Sinai.
On Friday, 28 soldiers were killed and another 30 injured when a car bomb exploded at the Karm Alkwadis security checkpoint in Sheikh Zuweid in North Sinai. Hours later, three security personal were killed when militants opened fire at a checkpoint in nearby Al-Arish.
The president declared a three-months state of emergency in parts of North Sinai on Friday evening.
Addressing his remarks to the nation, El-Sisi said that it is important that the Egyptian people know that foreign forces aim to defeat the will of the military and of all Egyptians.
"We must know that this terrorist attack was supported by foreign hands to defeat the military that has been protecting the Egyptian people and their will," he said.
He also stressed that he knew that all these attacks would take place "even before 3 July 2013," in reference to the date of the ouster of Islamist president Mohamed Morsi.
"We had a choice - either the people or the army had to confront terror. We chose that the army carry out the mission," said El-Sisi.
The former military chief said that his country is undergoing an "existential war" and stressed that the real danger lies in the foreign hands that wants to intervene between the armed forces and Egyptians.
"Reforming the new Egypt will necessitate a lot of blood, work and effort, so we all have to work closely hand-in-hand," El-Sisi said, adding that soldiers and civilians died and that there will be more and more people dying.
El-Sisi also said that Egyptians must realise "how broad the conspiracy against us is."
The former military chief, who was elected president this summer, said that recent work in different fields had been very fruitful at combating terrorism in Sinai.
El-Sisi said that if it hadn't been for the army's intervention in Sinai, the restive peninsula would have been a "cluster" of terrorism and extremism.
"I have noted before that the war in Sinai will last for a long time, as there are a lot of terrorists hiding in the peninsula, but this new level of attacks has put us in a new level of planning too in order to combat the terrorism there," stated El-Sisi.
"There are attempts to drive a wedge between the people and the army. No-one will be able to divide the Egyptian people and its army."
The president said despite the recent attacks "much has already been done to combat terrorism."
El-Sisi said that the government "was ready to take action to solve the problem on the Egypt-Gaza border at the roots."
He ended his speech by assuring Egyptians that the armed and police forces will work to combat the terrorism and by extending his condolences to all Egyptians for the great loss.
Over 40 security personnel have been killed in attacks in the Sinai Peninsula this week, including the two attacks on Friday.
A militant insurgency by jihadist groups in the peninsula has become more active since the ouster of Islamist president Mohamed Morsi in 2013. Hundreds of police and soldiers, as well as militants, have been killed.