"Will not leave Sinai for terrorists and "Sinai would either be for Egyptians or we would rather die," he said in a statement aired on the state TV commenting on the recent terrorist attacks in Sinai.
Sisi's remarks came right after his meeting with the Supreme Council of the Armed Forces (SCAF) to discuss Thursday's terrorist attacks that killed over 30 Egyptian security men and injured dozens in the restive Sinai Peninsula and the methods to combat growing terrorism in the region.
"Egypt is facing the strongest secret organization in the world," said Sisi, referring to the currently-blacklisted Muslim Brotherhood group from which ousted Islamist president Mohamed Morsi hailed.
Sisi pointed fingers at the Brotherhood group for the recent deadly anti-security attacks despite that the Sinai-based al-Qaida-inspired Ansar Bayt al-Maqdis (ABM) group claimed responsibility for them.
Sisi said that the country and the whole region would have turned into flames if the Brotherhood had remained in power. "They wanted to either rule you or kill you."
The Egyptian president urged the judiciary to make fast procedures in accordance with Egypt's war against terrorism.
Sisi said that before the ouster of Morsi in mid-2013, a leading Brotherhood figure threatened him that if he did it Islamists would come from Afghanistan, Pakistan, Syria, Libya and others to fight against him.
"We know those who helped you and provided you (with weapons) and we will not let them go," Sisi said addressing those who carried out the recent terroist attacks in North Sinai, whose responsibility is claimed by the ABM group.
As for Egypt's economic summit scheduled to be held in Sharm El-Sheikh in March, Sisi reiterated that the summit will be held as planned.
Sisi expressed certainty that the state will win over terrorism in the end and that Egypt will grow stronger.
After meeting with the SCAF earlier on Saturday, Sisi made a presidential decree to form a unified military leadership for the region of eastern the Suez Canal for fighting terrorism.
Egypt has recently extended a curfew in many parts of North Sinai for another three months due to the unstable security conditions in the area and the recurrent terrorist attacks targeting security men and premises.
The government has also been evacuating houses at the borderline with the Gaza Strip to create a buffer zone and intensify anti-terror military operations in the northern part of the peninsula.
The anti-security attacks mounted in Sinai and other parts across the country since Morsi's ouster in July 2013 and the following crackdown on his supporters that left about 1,000 killed and thousands more arrested.
The attacks targeting security forces have left hundreds killed. Most of the attacks were claimed by the ABM group that has recently changed its name to "Sinai State" after declaring loyalty to the Islamic State militant group in Iraq and Syria.
Since Morsi's removal, his loyalists have been staging anti-government protests denouncing his ouster as "a coup." The Muslim Brotherhood, Morsi's power base, was blacklisted by the new leadership as "a terrorist organization."