India is seeking to double the German investment in the country over the next five years from the current 9.5 billion Euros and also wants a two-fold increase in the number of German companies, a former Indian Ambassador to Germany said here on Tuesday.

In recent times, India has attracted about 74 German companies which have business plans worth investment of $1 billion, Gurjit Singh told PTI as Prime Minister Narendra Modi held talks with German Chancellor Angela Merkel and signed eight agreements.

There are opportunities for German companies in India's infrastructure, defence sectors, railways, smart cities, renewable energy, ports and shipping, coastal shipping and inland waterways, he added.

"German investments in India is about 9.5 billion Euros, made during 2000-2016, which can be doubled to 18 billion euros may be over the next five years. We (also) want to double the number of German companies in India to 3,600 from 1,800," according to Singh who retired in March this year after serving 37 years in foreign service with Germany being his last posting.

Singh said German companies were also being urged to form consortiums with European and non-European companies to undertake mega projects in India, especially their participation in smart cities which would require different disciplines, expertise and technologies.

Germany's small and medium size companies, known for having good technologies, should take the lead in forming these consortiums, he pointed out.

Joint ventures between German and Indian companies could also lead to building up consortiums for undertaking mega projects in the country, he said after addressing the Institute of South Asian Studies, a think tank at the National University of Singapore.

Overall, the European investments in India should also be doubled to at least 1.5 per cent from the current nominal level of 0.7 per cent of their global investments, according to Singh who has also served as ambassador to Indonesia, Ethiopia, ASEAN and African Union.

He said Modi's ongoing to visit to Germany is well timed and would boost bilateral relations between the two countries.