"Notes and orders will normally be recorded on note sheets in the notes portion of the file and will be serially numbered. All category of officers will use either blue or black ink in signing notes and drafts," the Ministry of Personnel, Public Grievances and Pensions said in an order.
Other staff and officers below the level of Joint Secretary were earlier allowed to use black or blue ink only for all the official purposes.
The Ministry has also instructed all central government offices to discontinue the use of telegrams as a mode of communication.
The instruction was issued over a year after the government decided to close the telegram service. The 163-year-old telegram service was closed in July last year.
The telegrams were used by the government for communicating with outstation parties in matters demanding prompt attention.