Both Derby and Nottingham Forest want the 26-year-old central defender and Blackpool look close to getting a fee that will persuade them to sell up.
Pride Park boss Nigel Clough is allowing Lewin Nyatanga to join Bristol City and is also in talks with Claude Davis to terminate the Jamaican's contract, ahead of a third bid for Barker.
"We're still talking," Clough told BBC Radio Derby.
"Hopefully we are getting closer to a deal."
At present, full-backs look to be Billy Davies' top priority, while he has also admitted an interest in Polish midfielder Radoslaw Majewski.