Printing of the Union Budget, one of India’s most secret documents, began on Thursday, with the traditional halwa ceremony in which Finance Minister Arun Jaitley participated.

As part of the decades-old ritual, halwa is prepared in a large vessel inside the ministry premises and distributed to entire staff. After this ceremony, which takes place a week or two before the Budget, around 100 officials and staff directly involved in the Budget-making process are locked in the basement of the ministry.

They are cut off from the outside world till the time the Finance Minister presents the Budget in Parliament. Barring very senior officials, who are issued special passes to go and come out of the ministry, rest of the Budget-making staff are not even allowed to talk to their family members till the Budget presentation.

No mobile phones are allowed in the basement where the printing takes place. There is only one landline phone that too without the outgoing call facility. The basement is heavily guarded and sometimes surprise checks are conducted by Intelligence Bureau officials.

The computers used in the printing process are cut off from the National Informatics Centre server to ensure there is no data leak from any point.

This year, the lock-in for the officials has come a month in advance as the government led by Prime Minister Narendra Modi has decided to present the Budget on February 1, instead of the traditional last day of February.