Cairo - A previously unknown pyramid estimated to be 4,300 years old was discovered in Egypt's desert, Egypt's Secretary General of Antiques Zahi Hawass said on Tuesday.

The pyramid, five metres high with a square base of 22 metres on each side, is believed to belong to Queen Seshseshet, mother of King Teti, the first king of ancient Egypt's Sixth Dynasty, Hawass said.

Teti came to power in 2323 BC.

The pyramid is the 118th discovered in Egypt and originally was 14 metres tall, Hawass said at a press conference.

The tomb is located near the pyramids of two of Teti's wives, Queen Kuit and Iput I, and only metres away from the Saqqara step pyramid, the world's oldest stone pyramid.

"We have previously discovered two pyramids that belonged to Teti's wives, this made us think that the only missing one is that of his mother," said Hawass.

Archeologists have never found a tomb for Teti's mother at the Saqqara burial ground, south of Cairo.

"We hope to find inscriptions with Seshseshet's name on it," Hawass said, referring to the queen is known from mentions of her name in a medical papyrus. The papyrus contained a recipe for a treatment for her hair.

The pyramid was found when dozens of men clearing dirt and stones happened upon what appeared to be an entrance.

"Since we found this mound of sand we knew that there was something underneath it", said Hawass. He said the Egyptian team had discovered the pyramid two months ago.

"In about two weeks we will enter the queen's burial chamber," said Hawass.

He added that no treasures are expected to be found as most of the chamber's contents would likely have been stolen.