OSLO, Sept 20 (Reuters) - Sweden's financial markets regulator has asked pension fund provider Alecta whether it had taken into account interest rate and currency risks before investing into a subsidiary of property group Heimstaden , newspaper Svenska Dagbladet reported.

The Swedish Financial Supervisory Authority (FSA) last week said it will investigate whether Alecta complied with rules and regulations when it invested 50 billion Swedish crowns ($4.5 billion) in Heimstaden Bostad.

Correspondence between the FSA and Alecta showed that the regulator questioned whether Alecta had taken all relevant risks into consideration when calculating capital requirements, the newspaper said in a report late on Tuesday.

Alecta, one of the largest shareholders in Heimstaden Bostad with a 38% stake, has said the property company was in need of more cash, and that it may contribute additional capital.

Heimstaden's difficulties are the latest blow in a worsening property crisis in Sweden where developers are grappling with large debts, rising interest rates and a wilting economy.

Alecta did not immediately respond to a request for comment on Wednesday.

Sweden's biggest pension fund provider last week said it would fully comply with the FSA investigation and that its investment in Heimstaden Bostad amounted to around 4% of its assets. ($1 = 11.1670 Swedish crowns) (Reporting by Terje Solsvik; editing by Miral Fahmy)