Swaraj was speaking at a public meeting organised at Hanamkonda here as part of the BJP's campaign for Parkal assembly bypoll on 12 June in Andhra Pradesh's Telangana region.
Hitting out at TRS, Swaraj said the sub-regional party was deceiving the people of Telangana by aligning with parties like Congress, TDP on different occasions.
Parties like TRS, with two MPs in Parliament, can not achieve separate statehood, she said, adding it is possible only with the national party like BJP which is committed to the cause.
TRS should explain to the people how it can achieve separate statehood without support of a national party like BJP, Swaraj said.
"The UPA government went back on its word to create separate Telangana though it announced on 9 December, 2009 that it would take steps for the formation of the separate state," she said.
Swaraj thanked the people of Mahabubnagar for electing the BJP candidate in a bypoll held in March.
Having won Mahabubnagar bye-election, the BJP is now trying to expand its presence in Telangana by winning the Parkal bypoll.
Swaraj, who had strongly spoken in favour of separate Telangana in Parliament, is the BJP's star campaigner in the region.
The Parakal bypoll is necessitated as the sitting Congress MLA was disqualified by Assembly Speaker for switching loyalty to Kadapa MP YS Jagan Mohan Reddy and voting against the Congress government during a floor test in December.
Byelections to 18 assembly constituencies including Parakal and one Lok Sabha seat will be held on June 12 in Andhra Pradesh.