India's Prime Minister Manmohan Singh reshuffled his Cabinet on Sunday in a bid to overhaul his government's image ahead of state and national elections over the next 18 months.

Seven new ministers and 15 junior ministers took the oath of office at a brief ceremony to mark the changes aimed at bringing in younger faces into the Cabinet.

Former law minister Salman Khurshid was named as external affairs minister, while Ashwini Kumar, a junior minister, was elevated to the Cabinet with the law and justice portfolio.

Five senior ministers had resigned over the weekend to allow the introduction of younger new faces in the ministerial lineup.

The long-awaited Cabinet changes gained urgency after the Congress Party-led coalition government was hit by a wave of corruption scandals. The revamp also filled several vacancies after a key ally opposed to recent economic reforms quit the coalition.

However, Congress party star campaigner Rahul Gandhi was not part of the new Cabinet. Congress party leaders said he would concentrate on reviving the fortunes of the party before national elections in 2014.

Gandhi, a scion of the India's politically powerful Nehru-Gandhi family, is the son and grandson of two prime ministers. He is presumed to be a prime minister-in-waiting, but so far he has held no government positions.

"I would have been happy to include Rahul in the Cabinet, but he has other preoccupations in the party," Singh told reporters.

Singh said he had moved several people from their ministerial posts to strengthen the Congress party.

Congress lawmakers said the government wanted to change its image as a group of old men and the induction of young men and women into the government was to dispel this impression.

"This reshuffle is to bring in fresh faces and is an important step keeping in view the general elections in 2014," Milind Deora, a junior minister said Sunday.

The induction of younger lawmakers and the shuffling of ministerial portfolios were being viewed as a major makeover for Singh's government that has been hit by charges of corruption and lethargy even as provincial elections are due in 11 states in the coming year.

Several ministers were facing corruption charges stemming from scandals over the hosting of the 2010 Commonwealth Games, the sale of cellphone rights and allocation of coal fields that auditors said lost the country of billions of dollars.