But there are also specific fears about India's slowing economy, a lack of substantive reforms and its large current account deficit. That is reflected in foreign fund outflows from India's debt and equity markets since late May of $11.5 billion.
"The government must be weighing the pros and cons of various options available to them, which would be most effective in attracting capital," said Upasna Bhardwaj, economist with ING Vysya Bank in Mumbai. Options include the issuing of NRI bonds and encouraging state-run firms to raise foreign debt, she said.
"If attractive yields are provided, any of these options could be successful."
(Read more: Indian rupee hits record low, but some relief ahead)
Huge diaspora
India has taken some steps this year to try to attract foreign investment, such as easing registration rules and increasing ownership limits for long-term investors such as sovereign wealth funds.
Measures from the Indian stock market regulator aimed at curtailing speculative positions against the currency gave it some reprieve, but market participants are bracing for a rise in policy rates or other aggressive measures to attract foreign money.
"We understand that we need funds to finance our current account deficit but we do not want to send any signal of panic outside India," a second government official said.
"The rating agencies are already watching us closely, we have to manage the situation in a subtle manner," he said.
(Read more: India unhappy, but unshaken by rupee's plunge)
The government's first line of defence therefore would be to woo non-resident Indians, sources said.
NRIs lapped up bonds and deposits issued by India in 1998 and 2000, helping bridge massive gaps in India's funding needs. Now, with a current account deficit at a record 4.8 percent of economic output, the country needs all the funding it can get.
The government sources said India could consider raising the repo rate, the central bank's main policy rate, if the rupee falls towards 61-62 to the dollar, citing recent meetings between the government and the RBI.
The government is also considering allowing select companies such as state-run India Infrastructure Finance to raise up to $4 billion in debt abroad, they said.
The first official said state-owned banks are likely to be asked to raise funds from overseas markets to meet their capital needs.
"Even if 5-7 banks raise $1 billion each, it will help us," he said.