Ladakh was annexed by which ruler as part of the Treaty of Amritsar?

The Britishers signed a Treaty called Treaty of Amritsar in 1846, with Gulab Singh who ruled Jammu until then. In the Treaty, whole of Kashmir, Ladakh, Gilgit, Baltistan were transferred to Gulab Singh. He was made the Maharaja of Jammu and Kashmir and Ladakh also became a part of his kingdom.