Finance Minister Nirmala Sitharaman on Tuesday proposed to issue sovereign green bonds to mobilise resources as part of the government's borrowing programme. She said that outlay for capital expenditure has been stepped up by 35.4 per cent to Rs 7.5 lakh crore in FY'23.Effective capital expenditure will be Rs 10.68 lakh crore, or 4.1 per cent of GDP, in 2022-23, the finance minister said, adding public investment must take the lead to pump prime private investment and support demand.