He was speaking on the sidelines of a seminar on investment opportunities organised by the Haryana government as part of the 9th edition of Vibrant Gujarat Global Summit.
"This (opposition) unity is not going to last. They have united out of fear of Narendra Modi's popularity and the country's growing position in the world. This (opposition unity) is going to make no difference to the people," Khattar claimed.
"They (opposition parties) had looted the country for several years. They have united as they are not getting the opportunity to loot the country," Khattar added.
He was responding to a query on the Trinamool Congress-led mega opposition rally, titled 'United India Rally', held in the Brigade Grounds in Kolkata on Saturday.
He also mocked the opposition parties' lack of a leader acceptable to all constituents, and claimed it was a "baraat' (marriage procession) without a groom.
Speaking on economic issues, Khattar said his state was looking at investments and added that it had climbed up the ladder as far as ease of doing business rankings were concerned.
He said Haryana was now third on the ease of business ranking.
"We want to make use of Haryana's locational advantage to bring in investments. We took steps to make clearances and licences simple, from which people have benefited,"he said.