* To buy assets valued at 192 million euros
* Authorities still need to approve
PARIS, June 11 (Reuters) - France's leading private broadcaster TF1 said it had clinched a deal to buy digital assets valued at 192 million euros ($269 million) from smaller peer Groupe AB
The deal, in which TF1 will buy all of NT1 and double its stake in TMC to 80 percent, will boost TF1's position in the fast-growing digital sector and counter a decline in its flagship channel.
TF1 said on Thursday employee representatives had approved the deal but relevant authorities still needed to give their approval.
NT1 and TMC are both free-to-air digital terrestrial television (DTT) channels, a sector growing rapidly in France with 16.8 million households receiving DTT at the end of 2008.
TF1, which like free-to-air broadcaster rivals including Italy's Mediaset SpA and France's M6, relies on advertising, cut its 2009 sales outlook in April as an ad slump pushed it to a first-quarter operating loss.
While TF1 will keep its 33.5 percent stake in AB, management of AB will be granted a call option to buy TF1's stake for 155 million euros within two years.
In addition, TF1 will increase its stake in WB Television, a holding controlled by Berda, to 49 percent from 33.5 percent for 1.5 million euros. TF1 bought its initial 33.5 percent in AB in April 2007 for 230 million euros.
Groupe AB is majority-owned by Berda, who founded AB Productions with Jean-Luc Azoulay in 1977. They split in 1999. (Reporting by Marcel Michelson; Editing by Dan Lalor) ($1 = 0.7126 euro)