NEW DELHI (AFP) - India's ruling Congress party introduced into parliament on Wednesdsay its flagship subsidised food bill for the poor that it sees as key to winning a third term in office.

The populist programme - which the government says will add 230 billion rupees (S$4.8 billion) per year to the country's existing 900-billion-rupee food subsidy bill - is being introduced with an eye on elections due by May of next year.

The measure has been pushed strongly by the head of the ruling Congress party, Ms Sonia Gandhi, who has insisted on honouring a 2009 election pledge despite concerns about the impact on government finances and food prices.

The bill is expected to be debated next week.

But opposition outrage over the government's muted response to an attack overnight on Monday along India's border with Pakistan in which five Indian soldiers died and other political rows has raised speculation that the food bill could die on the order paper.

"Border security is more important than food security," leader of the main opposition Bharatiya Janata Party, Sushma Swaraj, told parliament.

The controversy over the attack, among the deadliest on Indian soldiers in Kashmir since a 2003 truce was signed, paralysed proceedings in parliament on Wednesday.

The government had hoped to win passage of the bill earlier but parliament has been regularly disrupted throughout Congress's second term in office by protests over alleged government graft and other scandals.

Despite two decades of strong economic growth, India still struggles to feed its population adequately, with a major survey last year showing that more than 40 per cent of children under five were underweight.

Critics of the food programme say that India can ill-afford such a costly subsidy burden at a time of slowing economic growth and when credit ratings agencies are eyeing the country's large deficit.

Opposition lawmakers had criticised the government for issuing an executive order last month to put the measure into effect.

But the government withdrew the ordinance before tabling the bill in parliament.