NEW DELHI: Congress MP Shashi Tharoor has said the UN remains indispensable even in the face of its "failures" over Gaza and Ukraine, asserting that the world body's challenge is to become more representative and responsive in a world that needs principled global cooperation more than ever.

Tharoor, who has served as the UN under secretary general in the past, said on Thursday that to abandon the United Nations would be to abandon the very idea of common humanity.

"We need to recommit ourselves to the UN. As someone who served the UN for three decades from 1978-2007, I witnessed first-hand its evolution from a Cold War battleground to a post-Cold War laboratory of global cooperation," the MP from Thiruvananthapuram said, delivering the 15th Desmond Tutu International Peace Lecture in Cape Town, South Africa.

"I was part of its efforts to protect refugees and its struggles to build peace.

I saw the UN falter in Rwanda, rise to the occasion in Timor-Leste and Namibia. I saw it struggle with bureaucracy and politics, yet persist in its mission to feed the hungry, shelter the displaced and give voice to the voiceless," Tharoor said.

"Today, when people decry its failures over Gaza and Ukraine, I acknowledge again that the UN is not perfect nor was it ever meant to be, and yet it remains indispensable," he said.

As someone who spent much of his adult life in its service, Tharoor said he remains convinced that the UN matters.

It matters to the refugees seeking shelter, to the peacekeepers standing guard, and to the diplomat negotiating a fragile truce, the former Minister of State for External Affairs said.

"It matters to all of us who believe that cooperation is not weakness and that justice is not luxury.

The UN remains an indispensable symbol of not perfection but of possibility, as (former UN Secretary General) Dag Hammarskjöld so memorably said, 'it was not meant to take mankind to heaven but to save humanity from hell'," Tharoor stated.

In the aftermath of its 80th anniversary last month, the UN's challenge is to become more representative, more responsive and resilient in a world that needs principled global cooperation more than ever, he said.

"To abandon it would be to abandon the very idea of our common humanity.

Our own survival and that of the only universal world organisation we have - the UN - depends not on nostalgia but on renewal, and that renewal begins with the recognition that in an interconnected world, no nation is truly sovereign unless all are," Tharoor said.

It is time for that moral reimagination of the UN, he added.

Tharoor also called for replacing tolerance with acceptance and cited the words and vision of Swami Vivekananda.

"I am a Hindu and I learn from the great preacher Swami Vivekananda, who took Hinduism to the world of the late 19th century, that Hinduism stands for both tolerance and universal acceptance.

We believe not only in universal toleration, he (Vivekananda) spoke but we also accept all religions as true.

This was a profound insight, and that too in the late Victorian era," Tharoor said.

"I, after all, went to school in India, studied history, and learnt that tolerance is a virtue, that a tolerant king is a good king because he allows you to believe what he doesn't believe in.

But in fact, Vivekananda was telling us that tolerance is a patronising idea.

It is saying that 'I have the truth', but I will magnanimously indulge in your right to be wrong'," he said.

What Vivekananda taught Hindus is that we must replace tolerance with acceptance, Tharoor said.

"That is, we must say, 'I believe I have the truth, you believe you have the truth.

I will respect your truth, please respect my truth'," he said.

In that, there is a great recipe for human and inter-religious co-existence, Tharoor said.

"His (Vivekananda's) vision was summarised in the credo 'Sarva dharma sambhav'. All religions are equal. Yet too often religion is reduced to boundary-making, to identity politics, to tribalism. We forget that the word religion comes from the word religare - to bound together," he said.