* Deutsche Bank has bought more Postbank shares - source
* Postbank shares up 4.9 percent
* Analysts see no need for quick action by Deutsche Bank
(Adds background, comment, share price)
FRANKFURT, June 8 (Reuters) - Deutsche Bank is not pursuing an accelerated takeover of Deutsche Postbank although it has bought more shares in the retail bank in recent weeks, a source familiar with the matter told Reuters.
Deutsche Bank, which owns more than 25 percent of Deutsche Post subsidiary Postbank as a result of its drive to bulk up its retail banking business, declined to comment.
Germany's biggest bank has built up its Postbank stake to nearly 30 percent -- the threshold for making a mandatory offer to all shareholders -- to take advantage of low share prices, the source said on Monday.
But it sees no point in spending billions on a complete takeover at this stage because it holds the option to aquire Postbank outright in a few years under a deal finalised in January, the source said.
Deutsche Bank would have to pay an estimated 1.5 billion euros ($2.1 billion) to buy the rest of Postbank in a mandatory tender, an option the Handelsblatt newspaper said was under consideration.
Postbank shares were up 4.9 percent at 17.43 euros by 1140 GMT.
"That is in line with our scenario that Deutsche Bank will increase its share to more than 30 percent and will make a takeover bid to the free float shareholders of Postbank by late summer (August 26 at the earliest, six months after Deutsche paid 22.0 euros (per share) for 50 million Postbank shares from Deutsche Post)," LBBW said in a note raising Postbank to a "buy".
"With an early takeover offer, Deutsche Bank would avoid having to offer the free float shareholders 45.00 euros in three years, which is the price from the mandatory exchangeable bond due in 2012," it said.
The abrupt departure of Postbank CEO Wolfgang Klein last month underpinned these expectations, it said.
Other analysts were sceptical.
"Deutsche Bank is currently not interested to reach the majority in Postbank. Its premier targets are to weather the current financial crisis and to gain market shares in investment banking whenever it is possible," Merck Finck analysts said in a research note.
They and the Equinet brokerage said Deutsche would need to raise its capital should it proceed with a full takeover now.
Deutsche Bank and Deutsche Post in January agreed new terms for the bank's $6.5 billion takeover of Postbank, speeding up the deal and giving Post a temporary stake in Deutsche Bank. (Reporting by Philipp Halstrick, Writing by Ludwig Burger; Editing by Dan Lalor) ($1 = 0.7230 euro)