The Asian neighbours last enjoyed diplomatic relations at this level a decade ago.
Indian Foreign Minister Natwar Singh told The Hindu newspaper on Wednesday that he and his counterpart, Khurshid Mahmud Kasuri, in talks during an Asian conference in Qingdao, China, agreed to the reopening in principle. No dates were set.
The consulates in the two port cities would make travel easier for members of families split during the subcontinent's partition in 1947 and who now can seek visas only at embassies in New Delhi and Islamabad.
The Mumbai and Karachi consulates were shut down in 1994 amid a round of bilateral disputes including the Pakistani government's requests to take charge of the Mumbai home of the country's founder Muhammad Ali Jinnah.
Singh said the Jinnah House issue did not figure in his talks with Kasuri.
India and Pakistan had withdrawn their ambassadors from each other's capitals and sent a million troops to their borders after the Indian parliament was attacked in December 2001 by armed men allegedly backed by Pakistan.
Envoys were reappointed and the countries resumed bilateral talks, including over disputed Kashmir, after India's then prime minister Atal Behari Vajpayee offered Pakistan a "hand of friendship" in April 2003.
The peace process has continued after Vajpayee's Hindu nationalists lost elections this year to a left-leaning coalition, with the two countries set for a new round of negotiations this weekend on easing tensions.
India and Pakistan agreed on Sunday to set up a hotline to avoid nuclear confrontation and continue a ban on nuclear tests.