"America must apologise and accept their fault. Only then, will we be satisfied," Nath told reporters here.
On Wednesday, US Secretary of State John Kerry spoke to National Security Advisor Shivshankar Menon and expressed 'regret' over the incident.
In telephone call to Menon, Kerry expressed also hope that this isolated episode would not harm the close and mutually respectful ties between the two countries.
Earlier, New Delhi strongly contested the allegations levelled against Khobragade and protested against her arrest and strip search by U.S. Marshals.
Prime Minister Manmohan Singh termed the arrest and ill treatment meted out to Khobragade as deplorable, and hoped that the United States would understand India's loud and clear message on the issue.
External Affairs Minister Salman Khurshid told Parliament that the government fully stands by Khobragade and will bring her back and restore her dignity.
The Indian Government had, on Tuesday, announced several steps to strip American diplomats and their families of privileges, including withdrawing all airport passes and stopping import clearances for the U.S. Embassy.
The U.S. was also asked to provide a list of all Indian nationals working with its Consulates, including domestic servants, by December 23. Security barricades outside the embassy consulates and other institutions under the jurisdiction of the embassy was also removed.
Khurshid maintained that Khobragade was a victim of a conspiracy created by her maid servant Sarah Richards, who has been absconding.
Despite all efforts by New Delhi, police in New York has not been able to trace Richards till now, and Khurshid suspected that the maid was set up by conspirators under a definite plan to humiliate the diplomat.
He said the immediate concern of the government is that no further indignity is meted out to Khobragade.
The government, he said, is following all legal procedures to deal with the situation. Referring to the anger and anguish expressed by the members, Khurshid assured them that the government would not let them down.
He said the adverse U.S. action would be repulsed in the strongest possible manner.
Khurshid said the paramount concern of the government is to intervene effectively and strongly to protect Khobragade's dignity and honour.
He also assured the House that the diplomat will be brought back to India with all respect and every action would be taken to restore her dignity and modesty.
Earlier this week, political leaders cut across party lines to refuse to meet a U.S. Congress delegation till the diplomatic row is resolved.
Senior leaders like Lok Sabha Speaker Meira Kumar, Home Minister Sushil Kumar Shinde, Congress vice president Rahul Gandhi and BJP prime ministerial candidate Narendra Modi have refused to meet the U.S. Congress delegation.
National Security Advisor Shiv Shankar Menon cancelled meetings in Delhi with the delegation. Menon has described Khobragade's treatment as "despicable and barbaric."
Devyani's father, Uttam Khobragade, a former IAS officer, said: "My daughter is brave, but I am worried. There is more than what meets the eye. She has not done anything wrong."
Devyani Khobragade, 39, was arrested on Thursday. She has been accused of lying on the visa application for an Indian national who worked at her home from November 2012 to June 2013 for less than four dollars an hour.
--ANI (Posted on 19-12-2013)