Trump, who is the chairman and president of the Trump Organisation which is the holding company of his billions of dollars worth projects, described the domestic luxury realty market as the "cheapest in the world".
He said the changed investor sentiment after Modi's victory, has forced him to alter his licensing agreement with the Lodha Group which is developing 75-plus-storey luxury apartments in the city.
"I will invest a substantial amount in the Trump Tower Mumbai, in my individual capacity," Trump said without quantifying the amount to be invested.
He was in town to unveil the first sample flat at the 800- feet tall Trump Tower.
On his investment plans, the New York-based entrepreneur said he has lots of cash and that he is interested in owning properties in the country, most probably in the hospitality space.
"Our next destination could be Delhi for a high-end luxury residential property," he said.
Last September, the Mumbai-based Lodha Group had roped in the Trump Organisation to develop The Trump Tower in the group's upcoming property 'The Park', through a licensing agreement which also involves design.
The Park is a 17.5-acre plot at Worli in the central part of the city, which also has other projects.
Earlier, the Trump Organisation had tied up with Pune- based Panchashil Realty for a similar property in 2012 but smaller in size. This 22-storey residential twin-tower project would have 44 luxury single-floor condominiums and is slated to be ready by 2015.
The Trump Tower Mumbai has around 300 super luxury units in the three, four and five bedroom configuration, priced in the range of Rs 9 crore to Rs 18 crore.
Lodha Group Managing Director Abhishek Lodha said that the property is so successful that even before the first sample flat is ready, it has sold more than 100 units. He also said the first three floors have already been constructed and hopes to complete the project by the end of 2018.
Under the licensing agreement, the Lodhas would pay Trump a fee running into several crores of rupees for the license to use its brand name for the project.
In 2010, Trump had entered into a similar pact with the city-based Rohan Lifescape for a 65-storey building at Chowpatty in the southern fringe of the city, which was later terminated. The project had to be scrapped due to delays in project approvals after stricter coastal zone regulation norms came into effect.
The multi-billion-dollar Trump Organisation owns and manages marquee hotels, resorts, casinos and luxury apartments in New York, Miami, Toronto, Vancouver, Dubai, Rio de Janerio as well as Panama, among others.