Prime Minister Narendra Modi's economic diplomacy is likely to face a litmus test on Monday.

He is expected to meet visiting leaders of the Samyukta Loktantrik Madhesi Morcha (SLMM) --Mahant Thakur, Upendra Yadav, Rajendra Mahato and Mahendra Raya Yadav -- the outcome of which will be crucial to whether the 114-day blockade at the Raxaul-Birgunj border imposed by the Madhesis will be lifted or not in the near future.

The blockade has not only crippled life in Nepal but also generated animosity towards neighbouring India, given that the landlocked Himalayan state shares a porous, 1700 km border with its bigger neighbour and is dependent on it for supply of essential items like fuel, medicine and food.

On Sunday, the four leaders met external affairs minister Sushma Swaraj over dinner, before which they also met senior leaders of various political parties, including the Congress, JD (U) and NCP.

But the Madhesi leaders are unlikely to budge from their position, given the stakes involved back home.

"Entire Madhesi population is watching the UMDF delegation's movements in Delhi and the delegation's members will lose legitimacy on their home ground if they strike a compromise with Kathmandu at the bidding of Delhi," said a Madhesi source accompanying the delegation, according to The Hindu.

SLMM is the same as United Madhesi Democratic Front (UMDF).

To give a perspective, Madhesis inhabit Nepal's Terai region, whose 20 districts have a common border with Indian states including Bihar, Uttar Pradesh and Uttaranchal. Apart from speaking Hindi, they share a close cultural and ethnic affinity with India.

The Terai region reportedly accounts for about half of Nepal's 29 million (2013 figure), yet has been denied proportionate in the state's polity, a long-held grudge that has taken a sinister turn in the form of the blockade.

The new Nepali Constitution, promulgated on 20 September, 2015, provides for a 165-member Parliament, which will have 100 representatives from the hill and mountain region but only 65 from the Terai region.

The Madhesis are demanding, among others, increased political representation, proportional inclusion in state organs, correction in citizenship provisions and revision in federal boundaries, reports IANS.

With a perception in Nepal that the blockade has the tacit support of India, despite the Madhesi leaders saying it was "pointless to blame India for the obstruction of supplies to Nepal", the continued stalemate does not augur well for Modi, who has consciously focused on economic diplomacy in Asia and elsewhere. If it fails miserably here, it will have on impact on Modi government's efforts to boost trade with other SAARC countries who resent India's "hegemony" in the region.