Brasilia: It is set to be a week of hectic multilateral diplomacy for Indian Prime Minister Manmohan Singh, who arrived here Wednesday evening on a three-day visit to participate in two back-to-back summits of Ibsa (India, Brazil and South Africa) and Bric (Brazil, Russia, India, China) countries.

The Ibsa and Bric summits, which are held in different formats, aimed at securing a bigger say for top emerging economies in world affairs.

Besides multilateral diplomacy, Manmohan Singh, who arrived here from the US, will also hold bilateral talks with Chinese President Hu Jintao and Russian President Dmitry Medvedev.

Three multilateral summits in a week underline India's growing global stature, said a senior official.

Manmohan Singh, accompanied by his wife Gursharan Kaur, arrived on Wednesday evening on the second leg of his eight-day overseas tour from Washington where he participated in the 47-nation Nuclear Security Summit. He was accorded a red-carpet welcome at the Brazilian Air Force Base with the presentation of ceremonial Guard of Honour and 21-gun salute. Manmohan Singh was received warmly by Brazilian Defence Minister Nelson Jobim with the military band playing national anthems of the host country and India.

Manmohan Singh will hold wide-ranging talks with Brazilian President Luiz Inacio Lula da Silva, the host of the twin summits, and South African President Jacob Zuma in the trilateral format of Ibsa.

The fourth Ibsa summit, comprising three top economic powerhouses straddling three continents, was to culminate yesterday evening with a joint communique reflecting their shared positions on a host of global issues, including the international financial crisis and reform of global decision-making bodies.

All three Ibsa countries are aspiring for a permanent seat in the UN Security Council.

The three countries are expected to sign two trilateral MoUs in areas of solar energy and science and technology.

The second Bric summit, projected by Goldman Sachs to be the world's largest economies by 2050, will today also push for the democratisation of international bodies.