The legislator who had courted controversy when he was Porbander MP by brandishing a gun at a toll plaza last year, also tendered his resignation from the Gujarat Assembly.
With this development the strength of Congress had been reduced to 57 in the state assembly.
In December 2012 Congress had won 61 seats out of which one candidate died, while another winning candidate Soma Patel chose to remain an MP.
"I have tendered my resignation in protest of negative politics of Congress for the state of Gujarat. There prevails policy of favouretism in Congress. We, me and my son, have decided to leave this party and join the BJP which has under the able leadership of Narendra Modi, a Prime Ministerial candidate, taken Gujarat to new heights of development," Radadiya said after submitting his resignation to the state assembly speaker Vaju Vala.
Radadiya who was a MP from Probander had contested the assembly polls from Dhoraji and won with a narrow margin in December last year. He chose to remain an MLA and resigned from Lok Sabha.
In statement issued after his resignation, Radadiya claimed that Gujarat has faced injustice from the Union government.
"Since I was member of parliament from Congress I could not oppose the party in public. But I had made several representations to Congress leaders and concerned ministers. I personally believe that if Gujarat had got what was rightfully its, the progress would have been much more."
Criticising the Congress for having dual standards, the former MP said, "While well being of people of Gujarat is in the heart of Modi, pessimistic politics by the Congress has always brought injustice to the state."
"The state and the country has witnessed the development done by the Narendra Modi led governement in Gujarat. Despite attempts by the Congress, people have elected Modi for the third consecutive time. Modi-led BJP government is committed to development and we want to be part of that process," he added.
In October last year, Radadiya was caught on a CCTV camera pulling out a gun at a toll plaza in Vadodara. In the footage the politician was seen pulling out a gun, brandishing it and threatening employees at the toll plaza. A case was filed against the leader and is still pending. The MP has refused to apologise, justifying his action by saying he acted in self-defence.