Nay Pyi Taw: As Manmohan Singh arrived here Sunday for the first visit by an Indian Prime Minister to Myanmar in 25 years, it marked another milestone in this country's steady march out of decades of diplomatic isolation and military rule even as key questions remain about the sustainability of the political reform process.

Ever since President Thein Sein, a former military General now heading a nominally civilian government, assumed office in March last year, he has surprised cynics by initiating a slew of political and economic reforms seeking to end Myanmar's international pariah status.

He freed more than 500 political prisoners, eased media censorship, restored workers' right to strike and allowed the National League for Democracy led by Nobel laureate Aung San Suu Kyi to take part in Parliamentary by-elections in April this year.

Singh is the latest in the galaxy of foreign leaders to travel to Myanmar since the political reforms were set in motion over the past one year.

Among the other dignitaries who had visited Myanmar since early this year are US Secretary of State Hillary Clinton, British Prime Minister David Cameron, UN Secretary General Ban Ki-moon, South Korean President Lee Myung-bak and Prime Ministers of Malaysia and Bangladesh.

US President Barack Obama has led world leaders in describing Myanmar's journey from military dictatorship to a fledgling democracy as a "flicker of progress" and opening a window of opportunity for the economic resurgence of a resource-rich but impoverished country.

The rush of foreign leaders and easing of Western economic sanctions is a vindication of India's consistent stand of a balanced approach to Myanmar defined by sustained engagement with the military junta and nudging it for political reforms and respecting Suu Kyi as a champion of democracy.

Once an outspoken supporter of Suu Kyi, India began engaging Myanmar in mid-1990s on issues relating to its own security in insurgency-hit northeastern states and energy requirement and as an apparent counter to China's growing footprints in this country.

Unfazed by Western criticism in the past for its engagement with Myanmar's former military regime, India has argued that sanctions on Myanmar are counter-productive.

At the heart of all discussions between foreign leaders and Myanmar's leadership has been the economic ties and cooperation in energy, development of natural resources and other sectors, including the lucrative tourism.

The US and European Union have moved to relax economic sanctions on Myanmar to reward it for its transition from oppressive military rule, particularly after NLD swept parliamentary bypolls in April this year. However, the US has been less cautious than EU.

Despite the remarkable political reforms Myanmar has seen in the last one year, concerns remain over the future shape democracy in this country could take and the role of the military entrenched for more than four decades.

After NLD and Suu Kyi made their debut in Parliament in April this year, 22 years after her party was prevented from assuming power following a landslide electoral victory in 1990, it represented another turning point in a fragile detente between the democracy icon, who has remained a political prisoner and has now turned an office-holder as the main opposition leader, and the government of President Thein Sein.