Stoke have begun work on new contracts for Marko Arnautovic and Erik Pieters, chairman Peter Coates says.

Both players were signed in the summer of 2013 and have 18 months to run on their current deals.

"Yes, they are contracts we are working on at the moment," said Coates, quoted in the Stoke Sentinel.

"We are always aware of these things, of where we want to go with them, and are trying to make sure we get things done in good time."