Oxford United boss Chris Wilder has been given permission to speak with Portsmouth over the managerial vacancy at Fratton Park.
Oxford are one point clear at the top of the League One table, while Portsmouth sit four points above the relegation zone.
Oxford chairman Ian Lenagan told the club's official website: "We have allowed Chris Wilder to speak to Portsmouth, partly out of respect for Chris's long service at Oxford United and partly because we want our manager to be at Oxford United because he has the desire to be here, not because we prevent him speaking to other clubs.
"Chris and I have been entirely straightforward with each other and from the board's point of view we have made it abundantly clear that that we want him to continue doing the good job he has been doing at Oxford United."
Wilder joined Oxford in 2008 following spells with Alfreton Town and Halifax Town.