Frankfurt  - German book publishers on Thursday denounced this week's historic accord between Google and US authors, dubbing it "a Trojan Horse" which would make the US company the master of the world's knowledge.

Google, which has scanned 7 million books to include their contents in its internet search engine, announced Tuesday it would let US users read the pages of books that are out of print but are still in copyright.

Under the settlement with the US Authors Guild and the Association of American Publishers, royalties will be paid for past and future use of the books by Google.

Millions of the books are outdated and their authors dead, so a Google-funded book registry will be set up to discover who now owns the copyrights. Google said it hoped to reach similar deals to benefit Europe and Asia.

But the Boersenverein, the German booksellers and publishers association which has bitterly opposed Google for years, rejected the accord as a "creeping takeover."

"This accord is like a Trojan Horse. Google aims to achieve worldwide control of knowledge and culture," said Alexander Skipis, chief executive of the Boersenverein, in a statement.

"In the name of cultural diversity, this American model is out of the question for Europe," he said. It contradicted "the European ideal of diversity through competition."

The Boersenverein has funded a pay-for-use book-scanning service for German-language books, Libreka.

In the United States the Google accord has been widely welcomed, since the bulk of books existing today are hard to obtain, as they are no longer on sale and uneconomic to reprint though their copyrights have not expired.

At US public libraries, those books from recent decades will be visible in their entirety on library computers, while 20 per cent of those books will be visible to home users.

For readers in the rest of the world, Google will only be showing "snippets": about two lines of text at a time. (dpa)