shareholders rejected a $6.8 billion takeover bid from

Northrop Grumman

(NOC) - Get Report

on Friday.

Northrop said it would review its options over the weekend and issue a statement Monday morning. Both sides left open the possibility for further negotiations and potentially a better offer. At its annual meeting on April 24, TRW shareholders voted to give Northrop access to its books.

"The focus of our board has been on shareholder value," Philip Odeen, chief executive of TRW, said in a press release. "We are working with several parties. We have encouraged Northrop to participate in this process."

In late April, TRW rejected a sweetened $53-a-share buyout offer from Northrop Grumman, saying it was financially inadequate. At that price, TRW would have been valued at about $6.8 billion. Since that time, TRW's stock has risen above the $53 offering price, a sign shareholders expect a better deal.

TRW closed down 80 cents at $55 Friday, while Northrop ended off $1.02 at $122.38.