Singh is pitted against Jaitley from Amritsar Lok Sabha seat.
Referring to Jaitley's "frequent wish-list" of developing Amritsar as an important trading centre, the former Chief Minister said it required good neighbourly relations with Pakistan.
"But will it be possible with Modi already having spelt out his confrontationist agenda with India's neighbours, particularly Pakistan?" he said.
"Because Mr Modi is speaking an entirely different language (from Jaitley) that is purely jingoistic and confrontationist," Singh said.
"I am only trying to remind you that this is what happened when your party was in power. So think before you sell fake dreams to people, least you cut a sorry figure once again".
During his various poll meetings, Jaitley has promised to open the trade route between Amritsar and Lahore.