At their fourth summit, the leaders of the BRICS countries -Brazil, Russia, India, China and South Africa -also pushed for the creation of a new joint development bank as a counterpoint to Western-backed aid lenders.
"We agreed that a lasting solution in Syria and Iran can only be found through dialogue," Indian Prime Minister Manmohan Singh said in a closing statement at the one-day summit in New Delhi.
A summit declaration warned of the "disastrous consequences" of allowing the Iran standoff to escalate into conflict and stressed that the bloodshed in Syria could only be resolved by "peaceful means."
The declaration also voiced the bloc's united support for a Syrian peace process promoted by international envoy Kofi Annan.
Russia and China -which both wield vetoes on the UN Security Council -have stridently opposed using force or outside intervention to resolve the Syrian crisis or defuse Iran's nuclear drive.
The United States and its allies have been frustrated by a Sino-Russian veto in the Security Council on condemning Syria in stronger terms.
Other BRICS leaders attending the summit were presidents Dilma Rousseff of Brazil, Dmitry Medvedev of Russia, Hu Jintao of China and South Africa's Jacob Zuma.
High on the agenda was discussion on a proposal to create the grouping's first institution, a so-called "BRICS Bank" that would fund development projects and infrastructure in developing nations.
Though it remains in the planning stages, the new BRICS bank is envisaged as a potential counterweight to other multilateral lenders like the World Bank and the Asian Development Bank.
The declaration said BRICS finance ministers would examine the "feasibility and viability" of the proposal and report back before the grouping's next summit.
Mr Zuma said the bank was an idea welcomed by other African leaders as a new source of funding for key infrastructure projects, which in Africa have also attracted hefty amounts of Chinese cash.
"Such a bank has great potential to help us create good jobs," he said.
In order to help revive global demand and growth, developing countries "need access to capital," said Mr Singh who also called for expanding the capital base of the World Bank and other multilateral lending institutions.
"Institutions of global political and economic governance created more than six decades ago have not kept pace with the changing world," he added.
The BRIC name was first coined in 2001 by US investment bank Goldman Sachs to group together fast-growing economies and the group held its first summit in 2009. South Africa joined last year at the third summit in China.
But the bloc has struggled to speak with one voice on global issues -divided not only by geographical distance but also widely divergent political and economic systems.
While intra-BRICS trade expanded by 28 per cent last year to $230 billion, it still represents a small fraction of world commerce.
"Aside from impressive economic growth over the past decade and an individual desire for a greater say in the institutions of global economic governance, these disparate countries have little in common," Walter Ladwig from the British think-tank the Royal United Services Institute wrote recently.
The lead-up to the gathering at a luxury hotel in the centre of the Indian capital saw demonstrations by hundreds of Tibetan exiles protesting against the presence of Chinese President Hu Jintao.
On Monday, a 27-year-old activist set himself alight during an anti-Beijing demonstration before running screaming down a street in gruesome scenes captured by media.
He died on Wednesday, becoming the first person outside China to self-immolate and adding his name to a list of 30 others who have killed themselves since March to protest alleged repression by China in Tibet.