WASHINGTON (Reuters) - Egyptian President Abdel Fattah al-Sisi offered a rare acknowledgement of his close security cooperation with Israel in the Sinai peninsula during a U.S. television interview with CBS’ “60 Minutes” news program broadcast on Sunday.

FILE PHOTO - Egyptian President Abdel Fattah al-Sisi speaks during presidential session at Africa 2018 Forum at the Red Sea resort of Sharm el-Sheikh, Egypt December 9, 2018. REUTERS/Amr Abdallah Dalsh

The program said Cairo had asked the network not to air the interview but did not give further details.

Under Sisi, Egypt has quietly cooperated with Israel on security in Egypt’s Sinai, a desert peninsula demilitarized as part of a U.S.-sponsored 1979 peace treaty between the two countries but where Cairo’s forces now operate freely.

Acknowledging such cooperation with Israel can be a sensitive topic in Egypt.

Asked whether the cooperation was the closest and deepest that he has had with Israel, Sisi responded: “That is correct.”

“The Air Force sometimes needs to cross to the Israeli side. And that’s why we have a wide range of coordination with the Israelis,” Sisi said, according to a transcript provided by CBS.

Defeating militants in the Sinai and restoring security after years of unrest has been a key promise of Sisi, who was re-elected in March last year in a landslide victory against no real opposition.

Islamist militants have been waging an insurgency for years in the north of the peninsula, which lacks basic infrastructure and job opportunities. In contrast, the region’s southern coast is peppered with Red Sea tourist resorts.

Egyptian security forces have battled Islamist militants in the mainly desert region, stretching from the Suez Canal eastwards to the Gaza Strip and Israel, since 2013.

Asked why he had not managed to wipe the militants out, Sisi responded by pointing to the difficulties that the United States has faced in Afghanistan against the Taliban insurgency.

“Why hasn’t the U.S. eliminated the terrorists in Afghanistan after 17 years and spending a trillion dollars?” he asked.

Sisi’s critics accuse him of cracking down on all dissent, but supporters say tough measures are needed to stabilize Egypt, which was rocked by years of unrest after protests toppled veteran leader Hosni Mubarak in 2011.

In his interview with “60 Minutes,” Sisi denied that Egypt was holding political prisoners. CBS cited one rights group’s estimate of 60,000 political prisoners.

“I don’t know where they got that figure. I said there are no political prisoners in Egypt,” Sisi said.

“Whenever there is a minority trying to impose their extremist ideology ... we have to intervene regardless of their numbers.”