The inscription reads ya Muhammad (O Muhammad).
This panel has the same outline and basic layout as a small group of Safavid cut steel panels, one of which was in these Rooms from the collection of Professor Ehsan Yarshater, 20 April 1999, lot 63 and another, more recently, 17 April 2007, lot 120 A. Similar quatrefoil panels are found amongst the door fittings formerly in the Harari Collection said to be from the Dar-i-Imam in Isfahan (A.U. Pope, A Survey of Persian Art, Oxford, 1938, pl.1389). Another example is in the David Collection (Kjeld V. Folsach, Islamic Art: The David Collection, Copenhagen, 1990, no.349, p.208). Two further panels of that group were sold at Sotheby's, 22nd October 1992, lot 179.
Like the example sold in these Rooms in 2007, the present panel differs from previously published examples partly in that the central panel has a brief inscription, but much more than that, in the exquisite pierced reciprocal trefoil border. This motif was frequently encountered in the seventeenth century, on carpets, pottery and manuscripts as well as metal. Rarely however has it been so delicately worked as here.