Sadiq Khan is set to launch the country's biggest inquiry into foreign property ownership as a growing number of Londoners fear being priced out of the Capital.
The London Mayor said there is a need for transparency as more people are becoming concerned properties are being snapped up by foreign owners.
He said: "As more and more Londoners struggle to get on the property ladder, there are real concerns about the prospect of a surge in the number of homes being bought by overseas investors.
"It’s clear we need to better understand the different roles that overseas money plays in London's housing market, the scale of what’s going on, and what action we can take to support development and help Londoners find a home."
The Labour Mayor added: "Londoners need reassuring that dirty money isn't flooding into our property market and ministers must now make all property ownership in London transparent so we can see exactly who owns what."
The inquiry will focus on the scale and impact of different types of overseas investment in London, as well as examine how foreign cash has changed the market.
A key part of the research will include finding out who is investing and where the money comes from.
The news has not been welcomed by all those in the sector however, with Savills' world research department claiming that foreign investment helped the market during an economic downturn.
The estate agent: "Foreign buyers are often the focus in discussions about the housing crisis, but really they are only one element in an incredibly complicated picture.
"Without them investing in properties at the top end, we would not have been able to fund very much social or affordable housing since the financial crash."
However research by Goldsmiths University says the influx of foreign investment has led to the "gentrification of the city".
Mr Khan's announcement comes only a short time after a new Homes for Londoners team was set up by City Hall to investigate and oversee the building of more affordable housing.
