MTNL announced it couldn't fund the escrow account for the upcoming 5th semi-annual interest payment on its 7.78% Bond Series VIIC due to insufficient funds. While this signals liquidity challenges for MTNL, bondholders are protected. All MTNL bonds are sovereign-guaranteed by the Government of India. In case of default, the Debenture Trustee will invoke this guarantee, obliging the government to make the payment. This provides a strong safety net for investors.