Congress leader Gaurav Gogoi on Thursday took a sharp jibe at Assam minister Himanta Biswa Sarma over his joining the BJP in 2015.
"We are standing strong, loyal to Congress, even during its bad times. But, can Himanta Biswa Sarma swear in his heart that he would not desert BJP in its testing times, like he did with the Congress?" Mr Gogoi said at a gathering of party workers in Assam's Morigaon district.
In 2015, Mr Sarma had quit the Congress to join the BJP with a bunch of loyalists ahead of the 2016 Assam assembly elections.
Once an architect of the Congress's repeated wins in the state, Mr Sarma had played a vital role in BJP's ascend to power in Assam and other north-east states.
Political observers believe one of the main reasons for Mr Sarma's switch of loyalty was late ex-chief minister Tarun Gogoi's favouritism towards son Gaurav.
The Congress has announced its Mission 101 plus for the upcoming Assam assembly elections.
"The Congress party and its partners in the grand alliance will get 101 plus seats," said senior Congress leader Jitendra Singh.