An impression of a seal bearing the name of the Biblical King Hezekiah of Judah has been discovered in Jerusalem - in what is being hailed as the first such discovery of its kind.

The tiny oval piece of clay bearing the image of the seal was discovered during the excavation of an ancient rubbish dump being conducted by the Hebrew University of Jerusalem's Institute of Archaeology at the foot of the southern wall of the Temple Mount.

The seal impression features a sun with two downturned wings and Egyptian ankh symbols, symbolising life, as well as an inscription which reads "Belonging to Hezekiah (son of) Ahaz king of Judah".

The piece of inscribed clay, known as a 'bulla', is thought to show the personal seal of the king and would have originally been used to seal a rolled papyrus document. Marks from the thin cords used to tie up the scroll can be seen on the bulla.

The refuse dump has been dated to the rule of King Hezekiah, who ruled in Judah between 727 and 698 BC, or shortly after. Dr Eliat Mazar, who is directing what are known as the Ophel excavations, said that while seal impressions bearing King Hezekiah's name have been "known from the antiquities market since the middle of the 1990s" - some of which have depicted a winged sun, the find represents "the first time that a seal impression of an Israelite or Judaen king has ever come to light in a scientific archaeological excavation".

The bulla, which measures 9.7 by 8.6 mm in size and is only three millimetres thick, was found along with 33 others imprinted from other seals. Some bear Hebrew names and their reverses show marks of coarse fabric and thick cords, meaning they were probably used to seal sacks containing foodstuffs.

King Hezekiah was the 13th king of Judah, which lay to the south of the larger Kingdom of Israel. The son of Ahaz, he was king during the invasion and siege of Jerusalem by the Assyrian King Sennacherib in 701 AD. The prophets Isaiah and Micah were both active during his reign.