NEW DELHI (AFP) - Mr Narendra Modi prepared to take the oath of office as India's prime minister on Monday at the start of a new era hailed by his Pakistani counterpart as an opportunity to end decades of regional instability.

Ten days after winning the most powerful mandate for 30 years in a landslide election win, Mr Modi signalled his bold intentions by reportedly cutting a swathe through the ranks of government with a radical cabinet revamp.

And as stocks markets rose at the prospect of a pro-business leader taking the helm of the world's largest democracy, the prime minister of India's nuclear-armed rival gave voice to a widespread sense of optimism.

"It is a great moment and a great opportunity," said Pakistani Prime Minister Nawaz Sharif, who is a guest for the swearing-in of a man with an image of being a hardline Hindu nationalist.

"This is a chance to reach out to each other. Both governments have a strong mandate," Mr Sharif told India's NDTV network, according to a transcript provided by the Pakistan High Commission.

"Both countries should rid the region of instability and security that has plagued us for decades."

After a decade of left-leaning Congress party rule, the 63-year-old Modi is expected to steer India firmly to the right in the next five years.

Mr Modi, leader of the Bharatiya Janata Party (BJP), paid a visit to the memorial of India's independence hero Mahatma Gandhi early Monday, before then stopping to meet Atal Bihari Vajpayee, his party's only previous premier, who is confined to his home at the age of 89.

Mr Modi's new cabinet was expected to be announced ahead of his inauguration at an evening ceremony and he indicated in a statement that the number of ministries would be sharply reduced.

"Keeping our commitment to 'Minimum Government, Maximum Governance' we have made an unprecedented & positive change in Ministry formation," he also said on his official Twitter feed.

Reports said that Mr Modi, son of a tea-stall owner, planned to slash 26 government positions. Close ally Arun Jaitley was widely tipped as finance minister and the BJP's most senior woman leader, Mrs Sushma Swaraj, as foreign minister .

"Team Modi" would have 23 full-rank cabinet ministers, down from his predecessor Manmohan Singh's 28, while the number of junior ministers would be pruned to 22, the reports said.

The BJP secured the first majority since 1984 at the election, trouncing the scandal-plagued Congress on a promise of reviving manufacturing and investment to create millions of jobs.

Mr Modi's pledge to overhaul the flagging economy won over voters, along with his rags-to-riches story and reputation as a clean and efficient chief minister of prosperous western Gujarat state.

"The country needs to be steered in the right direction now and only Modi can do it. He's got a strict school headmaster quality about him," Ms Kavita Lal, a 32-year-old IT professional, told AFP as she took the New Delhi metro on Monday.

Like many, she mocked the prime ministership of outgoing 81-year-old Singh who rarely spoke to the media during 10 years in power and was widely seen as lacking authority.

"It just seemed like for the last 10 years we had no leader in the country," she said.

During campaigning, opponents and critics said the 63-year-old leader would favour the Hindu majority at the expense of the country's 150 million Muslims and other religious minorities.

Many Muslims remain deeply suspicious of Mr Modi, who is tainted by communal riots in Gujarat in 2002 that killed more than 1,000 people, mostly Muslims. He has denied he failed to stop the bloodshed and a court investigation found he had no case to answer.

Hindu and Muslim mobs clashed in the main Gujarati city of Ahmedabad on Sunday night, apparently sparked by a car accident during a marriage procession. Four people were injured.

Since election results on May 16, the bachelor has been at pains to put his divisive past behind him and appear inclusive.

In a rare sign of emotion last week, he choked back tears as he promised to try to live up to the expectations of all Indians including "our weakest and poorest" during a speech in parliament.

The invitation to Mr Sharif was seen as a significant olive branch to India's Muslim neighbour and it marks the first time that a leader from either country has attended his counterpart's inauguration since independence in 1947.

India and Pakistan have fought three wars and bilateral ties broke down after the 2008 attacks by Pakistani gunmen on Mumbai in which 166 people were killed.

Mr Sharif, who has hailed Modi's "impressive victory", accepted the invite which was extended to all heads of government from the South Asian Association for Regional Cooperation (SAARC) which includes Pakistan.