New Delhi:  The BJP, in the state Assembly of Sikkim, has been propelled to the status of main opposition after 10 MLAs of the Sikkim Democratic Front joined the BJP on Tuesday, The BJP had not won a single seat in the recent Assembly polls.

The MLAs joined the party in the presence of its general secretary Ram Madhav, who is in charge of party's affairs in the north east after meeting BJP working president JP Nadda.

Madhav told reporters that the SDF had a strength of 13 MLAs and its legislature party decided to merge with the BJP.

The BJP is running government as the main party or in alliance with regional parties in all the northeast states except Sikkim and this development has pushed the party closer to power there as well.

Two-thirds or more numbers of the MLAs of a party can join another party without violating the anti-defection law.

The SDF headed by Pawan Kumar Chamling ruled the state for over 25 years, making him the longest-serving chief minister of the country but he lost power in the recent elections.

The party won 15 seats while its rival Sikkim Krantikari Morcha (SKM) won 17 in the 32-member Assembly. Since two of the SDF MLAs had won from two seats, they resigned from one seat each, reducing the party's strength to 13 in the Assembly.

The SDF was a saffron ally earlier but now SKM has replaced it as a member of the BJP-headed North East Democratic Alliance.

The MLAs who joined the BJP include Dorjee Tshering Lepcha, who served as a minister in the Chamling government for three terms and is a five-time MLA, and three-time MLA Ugen Gyatso.

Lepcha said they were impressed with the "look east" of the Narendra Modi government, as he highlighted that his state is bounded by China, Bhutan and Nepal.

This is the first time that MLAs of a regional party in Sikkim has joined a national party "en bloc", he said.

"We want lotus to bloom in Sikkim," he said, referring to the BJP's election symbol.

Madhav said the BJP will play the role of a constructive opposition in the state.

The BJP's immediate challenge in the state will be the byelections to three seats.