The engagements between the two NSAs have been the only form of any high-level contact between India and Pakistan in the past few years.
An intervention by NSA Ajit Doval and his counterpart Nasir Janjua helped India and Pakistan arrive at the March 30 rapprochement which has ended - for now - the standoff over harassment of diplomats and other staff.
Sources told TOI that a telephonic conversation between Doval and Janjua on March 26 finally sealed the agreement between the two countries that the matter be resolved under the 1992 Code of Conduct (CoC) for the treatment of diplomatic/ consular personnel in India and Pakistan.
Indian high commissioner to Pakistan Ajay Bisaria and his counterpart here Sohail Mahmood had worked hard in Islamabad and Delhi respectively with local authorities to arrive at the understanding that the CoC be revived to address issues related to diplomats and diplomatic premises.
Although few and far between, the engagements between the two NSAs have been the only form of any high-level contact between India and Pakistan in the past few years. The last substantive dialogue Doval and Janjua was in December 2017 in a meeting in Bangkok.
In the latest conversation, they also discussed the overall situation in bilateral ties and agreed to remain in touch.
While Doval strongly underlined India's position that the raid on an Indian residential complex under construction in Islamabad on February 15 was way outside the bounds of acceptable behaviour, Janjua asserted that this was the first time that even women and children of Pakistan diplomats were being harassed here.
India has also sought an assurance from Pakistan that it will not block the ongoing construction work in the Indian complex. Both India and Pakistan agreed that there was already a template in the form of the CoC which could be used for further negotiations over the issue.
The CoC upholds the "dignity and personal inviolability" of diplomatic/ consular personnel. It also clearly states that intrusive and aggressive surveillance and actions such as verbal and physical harassment, disconnecting of telephone lines, threatening telephone calls, pursuit in cars and unauthorised entry into residences shall not be resorted to.
For India, dialogue between the NSAs is important for addressing some of its key concerns over the issue of cross-border terrorism and also any flare up in Kashmir. Both India and Pakistan arrived at an understanding in 2016 that they were not going to make public any exchange between the NSAs. The only time they issued a joint press statement was after their meeting in Bangkok in 2015 in which Pakistan reintroduced the mention of J&K dispute. Earlier that year, then Pakistan PM Nawaz Sharif upset the Pakistan army by not specifically mentioning the J&K dispute in the joint statement issued after his meeting with PM Narendra Modi in Ufa.