"We have tweeted that the two leaders discussed a range of issues. A range of issues means a range of issues. I don't want to add anything further... I leave it to you to draw your conclusion," external affairs ministry spokesperson Gopal Baglay said.
The two-day G20 Summit saw the Indian side making "significant contributions" on resolve to counter terrorism and boost global trade and investment.
Mallya has been in the UK for months, escaping arrest warrants against him.
Arvind Panagariya, sherpa for India at the summit, tweeted about the "interaction".
The G20 leaders resolved to facilitate swift and targeted exchanges of information between intelligence, law enforcement and judicial authorities on operational information-sharing, preventive measures and criminal justice response.
Modi regretted that the international response to terrorism was weak and said more cooperation was needed to fight the menace.
Modi emphasised that it was necessary to work together for sustained global economic recovery.
Hosted by Singapore, the exercise was held on land at the now renamed "RSS Singapura - Changi Naval Base" and at a sea phase in the South China Sea.
A city like Davos in India would give a big boost to tourism, development, jobs and overall economy
Infosys chief Vishal Sikka also said that demonetisation has shown to the world that Indians are ready to adopt new technology disruptions.
According to Microsoft CEO Satya Nadella, data today shows that the world GDP growth is not "something great" and that calls for the need for new innovations like AI being taken very seriously.
India to see highest salary increase in Asia Pacific in 2017
Breaking his silence over the demonetisation issue, RBI Governor Urjit Patel on Sunday said the central bank is monitoring the situation on a daily basis and taking all necessary actions to "ease the genuine pain of citizens" with a clear intent to normalise the things as early as possible.
Adani is the fastest growing energy company in Asia-Pacific and the second fastest in the world
Former RBI governor admits to being a 'greenhorn' as he started his stint at the central bank.
The Rupee is 3.7 per cent undervalued on trade related basis.
India's retail sector has benefited from the rapid growth in e-commerce
Costs on real estate construction are seeing stability.
India must carry on structural reforms, the finance minister said.
Both countries have been working on administrative assistance.