Noting upcoming elections in Maharashtra, Haryana and Jharkhand, Sonia said the situation is challenging and "it is only if we keep nothing else other than party interests uppermost in our minds that we will regain our lost position".
Counting Punjab, Rajasthan, Madhya Pradesh, Chhattisgarh and Puducherry where Congress is in power, she said, these states must stand out as examples of sensitive and responsive governance, accountable and transparent administration.
"We must be seen to be fulfilling our manifesto commitments. If not, we will lose people's support with obvious consequences," Sonia addressed the meeting of party general secretaries, state in-charges, state unit chiefs and others here.
Attacking the BJP government over the economic slowdown and indulging in vendetta politics, she asked party leaders not be only aggressive on social media as "democracy was in peril" and the mandate was being "misused" by the government.
While beginning her speech, Sonia said: "We are meeting at a time when there is a prolonged economic slump, when job losses are mounting by the day, when the confidence of the investors is getting shakier by the day, when the government appears more and more clueless and insensitive by the day."
Referring to former Prime Minister Manmohan Singh's recently issued statement on the economy, she said: "We are also meeting at a time when vendetta politics is at its peak and when those who speak out against the ruling establishment are being threatened and intimidated. Each and every institution is being diabolically subverted."
"The voices of dissent are being silenced. Democracy has never been at greater peril than it is now. As I said a few weeks back, the mandate of 2019 is now being misused and abused in a most dangerous fashion.
"The electoral mandate is being misused and abused in a most dangerous fashion by the government. Appropriation of freedom fighters and leaders like Mahatma Gandhi, Sardar Patel, and B.R. Ambedkar with the sole aim of misinterpreting their true messages to further their nefarious agenda."
Sonia asked party secretaries to have a concrete agitational agenda on issues of pressing concern to the people whether they be economic or social, and that only being aggressive on social media is not enough.
"It is not enough to be active and aggressive on the social media even though that too is needed and we need to do that better. Far more important is to go to the people directly. Our resolve and resilience is under severe test. We cannot afford to let our self-confidence and morale falter."
She said that this was the time when it would become clear as to who are those steadfastly devoted to the Congress as an ideology (as a vehicle), for strengthening the nation, and those who look to the party only as an opportunity for self-advancement.
Sonia criticised those who left the Congress in recent times, saying they have revealed their "opportunistic character".
Recalling the regime of United Progressive Alliance (UPA) government and its achievements in dealing with the economic slowdown between 2007 and 2009, Sonia said "our government had taken the economy out of the slowdown during the economic recession".
She also recalled how during the UPA regime the Congress-led government was able to generate jobs.
Slamming the government, Sonia told the party that the BJP-led NDA government has been unable to save jobs in several sectors.
Sonia said that "the resilience and resolve of the Congress is being tested today. And we need to go to people."
This was the first meeting of Sonia with senior party leaders, a month after she was appointed the party's interim chief after her son and former Congress chief Rahul Gandhi stepped down from the top post taking moral responsibility for the party's defeat in the Lok Sabha polls.
The agenda of the meeting revolved around Gandhi Jayanti preparations, membership drive and party workers' training.
( With inputs from IANS )