Prime Minister Dr Manmohan Singh [Images] will receive US President George W Bush [Images] at the Palam Airport Wednesday evening. And Minister for Science, Technology and Ocean Development Kapil Sibal will be the 'minister in waiting' for President Bush's India visit.

Generally, the Indian prime minister is not protocol-bound to receive visiting state dignitaries.

Complete coverage: Bush in India

As per the Geneva Convention, which governs matters of protocol, a visiting head of state or government should be received by a vice-minister (minister of state in India) or higher.

However, if a ceremonial reception were to be held at the airport for the visiting dignitary, then a more senior representative needs to be present.

When former US President Bill Clinton [Images] visited India in March, 2000, then prime minister Atal Bihari Vajpayee [Images] did not receive him at the airport.

Instead, the then external affairs minister Jaswant Singh received Clinton. Singh is receiving Bush primarily because the prime minister currently handles the external affairs ministry. It also signals the importance the Congress-led government attaches to the Bush visit.

"Yes Dr Singh is going to receive President Bush at the airport," the prime minister's media advisor Sanjay Baru told rediff.com.

He said last month, the prime minister had received Saudi King Abdullah at Delhi's [Images] Palam Airport.

Interestingly, it may be recalled, that when US President D Eisenhower visited India in 1950s, the then Indian prime minister Jawaharlal Nehru not only received him at the airport, but also traveled with him in his car.

Sibal, who was promoted as a cabinet minister last month, was chosen by Dr Singh to fulfill a protocol obligation.

"It is an honour to be the minister in waiting for the US President's visit. I am getting information which I need to have on President Bush," Sibal told rediff.com. "I am doing whatever I am supposed to do," he added.

As 'minister in waiting,' Sibal will accompany President Bush from the time he arrives at Delhi airport till his departure to Pakistan on Saturday morning. Sibal will also accompany the US President to Hyderabad on Friday.

Sibal is considered an expert on India-US relations. He was earlier co-chairman of the Indo-US Parliamentary Forum and member, Board of International AIDS Vaccine Initiative, headquartered in the US. He was also a member, Programme Board of the Bill & Melinda Gates Foundation's Indian AIDS Initiative.

Becoming minister in waiting during high-profile state visits is considered an important honour.