Sharma told AFP that terrorism and trade were "separate issues" during a visit to Islamabad with a trade delegation, and added that the identity of the perpetrators was yet to be established. "I am sure that our investigating agencies will identify and bring to justice the perpetrators," said Sharma.
Despite Israel's claim that Tehran was responsible for the Delhi car bombing which seriously injured a female Israeli diplomat, Sharma insisted the matter had to dealt with through proper legal avenues.
"Let's be very, very clear, an act of terrorism has to be dealt as per the law," he said.
India said last week it would send a "huge" trade mission to Iran to explore business opportunities created by sanctions imposed by the West over the Islamic republic's disputed nuclear programme. Iran is India's second-largest oil supplier after Saudi Arabia, providing around 12 percent of the fast-growing country's crude needs.
India says it will abide only by UN sanctions, and will not implement those by individual nations or groupings.
The country has been examining ways to step up trade with Iran amid trouble in settling its oil bills from Iran as a result of the sanctions campaign that is drying up banking routes.
The European Union earlier this month agreed to an embargo on Iran's vital oil exports as part of an intensifying US-led campaign aimed at forcing Tehran to abandon its nuclear programme.