(Reuters) - France has proposed to give India a 1 billion euro ($1.4 billion) credit line to fund sustainable infrastructure and urban development projects, Foreign Minister Laurent Fabius said on Tuesday.

The credit line would be available over three years and would be delivered through the French Development Agency, Fabius, who began his India visit on Monday, told reporters in New Delhi.

India, which has said it needs $1 trillion of investment by 2017 to upgrade its creaking infrastructure, is keen to attract foreign development agencies and companies to help finance new roads, railways and cities. Prime Minister Narendra Modi, who took office in May, has vowed to focus on infrastructure.

"If you don't have the share of technology and the share of finance, you can develop brilliant ideas, may be brilliant, but (you will have) nothing concrete," Fabius said at an event about sustainable growth and climate change.

He is the first of a string of Western politicians due to visit India over the next few weeks for talks with Modi and his government, drawn in part by the prospect of lucrative defence deals that stalled under the last administration.

Fabius called on Modi, ahead of his visit to Mumbai later on Tuesday, and invited him to France.

During the meeting, Modi sought French involvement in areas including low-cost defence manufacturing, a government statement said.

Some countries find extending a credit line or investing through development arms a useful way to boost ties with India and also gain an early link to the South Asian nation's future infrastructure schemes.

Japan is a key investor in the Delhi-Mumbai Industrial Corridor, a mega infrastructure project that envisages dozens of new industrial zones and cities sprouting alongside a 1,483-kilometre highway stretch between India's biggest two cities.