Mr Singh, along with BJP president Amit Shah, have attended the swearing-in-ceremony of Conrad Sangma-led coalition government in Meghalaya, where the BJP is also part.
"There was a perception that only the Congress can survive in the Northeast. But now that perception has changed with the BJP's victory in the Northeast," he told reporters here.
In the recently held Assembly elections, the Congress was ousted from power in Meghalaya while the party could not win a single seat in Tripura and Nagaland.
The BJP got absolutely majority and two-third majority along with its ally IPFT in Tripura, it won 12 seats in Nagaland and will be part of the coalition government along with Nationalist Democratic Progressive Party (NDPP) there.
In Meghalaya, the BJP won two seats and is now part of the Sangma government.