PARIS (Reuters) -France's finance ministry is working on plans to close a tax loophole benefiting short-term furnished rentals such as Airbnb, Finance Minister Bruno Le Maire said on Friday.

Many big French cities are facing housing shortages and renting flats to tourists on platforms such as Airbnb is often blamed for reducing the supply of housing.

A trio of cross-party lawmakers last month called for rules regulating such rentals to be tightened and for an end to the more favourable tax treatment such rentals receive vis a vis normal long-term rentals.

"I have a hard time understanding the very favourable tax treatment for Airbnb. We are going to reform the tax rules and I will make proposals," Le Maire said on BFM TV.

"When a windfall gets too big and tax is too favourable, there is no reason to keep such tax treatment that leads to excess," he added.

A finance ministry official said that the plans were being worked on and it was not yet clear whether they would be included in the 2024 budget, which is likely to be published at the end of September.

Nearly 20% of people in the greater Paris region that do not already rent their home or part of it on Airbnb plan to do so during next year's Olympic Games in the French capital, according to a survey the platform commissioned from pollsters Ifop.

"Airbnb helps boost the income of thousands of French families, and 60% say the extra income helps them afford rising living costs," Airbnb said in a statement.

"We want to work with the French government on measures to make their lives easier - not harder - while working together to tackle the root causes of housing challenges," added Airbnb, which is a corporate sponsor of the Games.

(Reporting by Leigh Thomas; Additional reporting by Elizabeth Pineau; Editing by Louise Heavens and Mark Porter)