The 28-year-old, who is out of contract at the end of the current campaign, has been linked with a move to French side Toulon.
Cohen has confirmed that the Tigers are in talks with the England international over a new deal.
"He is our captain, our playmaker and a leader. He is a great bloke and we are very keen to keep him," Cohen told BBC Radio Leicester.
"We have had lots of conversations with Toby. Toby wants to weigh up lots of things, lifestyle, where he's at with England - all sorts of things.
"He will weigh up all those and has said he will come back to us within a timescale that will enable us to plan, and him to plan if necessary."
Flood joined the Tigers from Newcastle Falcons in 2008.