(Adds market reaction, company comment)
VIENNA, April 18 (Reuters) - U.S. property investment firm Starwood Capital Group launched its bid for minority stakes in Austrian property companies CA Immo and Immofinanz as it seeks exposure to markets in central and eastern Europe.
"Starwood Capital considers Austria, Germany and (central and eastern Europe) as attractive markets and is committed to increasing its real estate exposure there," it said on Wednesday.
Starwood, a private equity firm that says it has $56 billion in assets under management, last month said it wanted to acquire up to 26 percent of CA Immo and up to 5 percent of Immofinanz, at only slight premiums to their share prices at the time, minus any dividends paid before completion of the deals.
Starwood is offering CA Immo shareholders 27.50 euros ($34.02) per share, minus any dividend paid. The stock slipped 0.2 percent in early trading to 27.44 euros.
Immofinanz's shares rose 0.3 percent to 2.196 euros, above the 2.10 euros per share, minus any dividend, Starwood is offering.
Neither company had an immediate reaction to the offer, noting they had 10 trading days to comment.
Immofinanz last month dismissed the offer as too low, while CA Immo said it needed more information to form an opinion.
The offer for CA Immo runs to May 16, while the offer for Immofinanz lasts until May 30.
Together they are worth up to around 824 million euros ($1.02 billion), according to Reuters calculations.
Both partial tender offers are independent and are not contingent on any minimum acceptance threshold.
Immofinanz already owns 26 percent of CA Immo. It said in February it was considering selling that stake after it effectively abandoned its plan to take over the company.
Starwood has said it supports both companies' management teams and does not plan to acquire a majority stake in either firm. Both will remain listed on the Vienna Stock Exchange.
$1 = 0.8083 euros Reporting by Francois Murphy, Michael Shields and Alexandra Schwarz-Goerlich, editing by Louise Heavens and Jason Neely