Mr Yeddyurappa's comments come as dissident activities of the MLAs intensified in the Congress over not getting ministerial berths.
The former chief minister, who is also the state BJP chief, asked his partymen to work as a strong opposition and prepare for the 2019 Lok Sabha polls.
"Several disgruntled young leaders and leaders from Congress and JD(S) are eager to join the BJP," Mr Yeddyurappa said.
Addressing partymen, he said, "It is our responsibility to induct those who are disgruntled with the JD(S) and Congress and their style of administration in every assembly segment, and are willing to join the BJP, thereby strengthening the party in every constituency."
The BJP leader said the party has "complete strength" with 104 members in the assembly and "let's work as a "strong opposition."
As the assembly polls threw up hung assembly with the BJP emerging as the single largest party, the BJP had formed the government, but conceded the numbers game with Mr Yeddyurappa resigning on May 19 without facing the trust vote.
Following this, Congress-JD(S) post poll coalition formed the government in the state, under the leadership of HD Kumaraswamy.
Calling upon BJP Yuva Morcha to strengthen the organisation at every assembly constituency level, Mr Yeddyurappa said that "by doing this let us prepare ourselves for the Lok Sabha election."
With his government facing birth pangs of coalition politics, Mr Kumaraswamy yesterday stepped in to check the disquiet among newly elected Congress lawmakers who were left out during the Cabinet expansion, but they remained defiant.
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