Addressing the Congress Parliamentary party here, the first since the Lok Sabha elections in which the party got only 52 seats - a marginal increase over 2014's 44, she said several decisive measures to strengthen the party were being discussed, following the Congress Working Committee (CWC) meeting last week.

"In this time of crisis, we must acknowledge the numerous challenges confronting the Congress party. In an unprecedented crisis, lies an unprecedented opportunity. It is up to us to grasp it with humility and self-confidence, drawing the appropriate lessons from our defeat.

"The people of India expect us to honour their mandate by renewing and reinvigorating ourselves. Undeterred by the many challenges that lie ahead, we will rise again," she said.

Sonia Gandhi also praised the newly-elected MPs, saying each one had fought one of the hardest elections of their careers where all the odds were against them as they faced "an election machinery with unlimited resources, ability to manipulate public opinion and spread mischievous propaganda".

She also had words of encouragement for party workers, who were "its front-line soldiers" and had worked worked selflessly for the last five years, making "innumerable sacrifices in the face of unprecedented hostility from the ruling party".

The workers had carried the party's message far and wide and their "resilience" has led to 12.3 crore voters reposing their faith in the Congress, she said,

In remarks intended for Rahul Gandhi amid his insistence on stepping down as party chief owning moral responsibility for the Lok Sabha poll debacle despite the CWC declining his offer, Sonia Gandhi said "emotional messages were coming from all corners vindicating his leadership".

Saying he "had toiled night and day for the party", she thanked him "for his valiant and relentless campaign" and displaying his "fearless leadership by taking the Modi government head on".

"He (Rahul) highlighted the injustices carried out against farmers, workers, traders and small businesses, against the youth, women and the marginalised sections of our society.

"As Congress President, he earned the respect and love of every worker and crores of voters across the length and breadth of our country. Even as I speak, emotional messages are coming from all corners, vindicating his leadership. We all express our gratitude to him for his sincerity of purpose, his relentless effort, his hard work and leadership," she said.

On the way ahead, Sonia Gandhi said the party would support "progressive and inclusive policies but oppose the government strongly whenever they undertake divisive and regressive actions".

"The issues we raise in Parliament, must resonate in the minds of our party workers and with the public," she said, calling on the MPs to "have their finger on the pulse of the people" and "set the agenda in parliament".

"We are not going to let our guard down. We must hold the Government accountable to their promises. Progress is currently being measured through manufactured data. Progress must be measured with truth. We will continue to fight for truth and transparency," she said.

She said Congress will be an alert and responsible opposition. "We will hold the government accountable in Parliament. We will be at the forefront of the fight for the rights of the people, both in Parliament and on the streets."