The Indian action came amidst rising anger among political parties over the January 8 incident when Pakistani soldiers crossed Line of Control in Mendhar area of Jammu and Kashmir, killing two soldiers and mutilating their bodies.
Breaking his silence on the issue, Singh justified the decision to suspend visa facility, saying "after this barbaric act, there cannot be business as ususal with Pakistan".
He said, "Those responsible for this crime will have to be brought to book" and hoped "Pakistan realises this".
When pointed out that Pakistan was in a denial mode on the cross-LoC attack, Singh said, "we will keep trying".
Asked about options available to the government, he said these could not be discussed in the open.
After his tough talk at the Army Day reception, Singh met President Pranab Mukherjee and briefed him on the situation.
He also deputed National Security Adviser Shivshankar Menon to brief Leaders of Opposition in Parliament Sushma Swaraj and Arun Jaitley.
India was to operationalise the long-delayed visa-on- arrival facility to senior citizens of Pakistan today but quietly put it on hold indefinitely. The facility was to be accorded for those above 65 years crossing the Attari-Wagah border by foot.
Government sources said the decision was taken after several agencies sought clarifications on facilities to be offered to the Pakistani citizens.
The visa on arrival facility under the new visa agreement between India and Pakistan signed in September 2012 to ease cross-border travel as part of Confidence Building Measures.