Celtic have reported their profits of almost £12m are largely due to the sale of Virgil van Dijk as the board admitted the season so far has been "frustrating".

In interim results published on the London Stock Exchange, chairman Ian Bankier reported a profit before taxation of £11.7m for the second half of 2015.

He said the failure to qualify for the group stages of the UEFA Champions League was "frustrating" for the club but profits are up from almost £7m from the same period in 2014.

Mr Bankier said: "On the park, it has been a frustrating season. We are top of the Scottish Premiership and in the sixth round of the Scottish Cup but we fell short in the SPFL League Cup, being knocked out in the semi-final.

"In the European competitions, we were unable to progress beyond the group stages of the UEFA Europa League, having not qualified for the group stages of the UEFA Champions League."

He added: "Our profit on disposal of intangible assets of £12.6m (2014: £7.1m) largely reflects the transfer of the registration of Virgil Van Dijk to Southampton.

"Over the same period we reinvested in the playing squad, with £6.1m expended (2014: £5.7m) on the registrations of Scott Allan, Logan Bailly, Carlton Cole, Ryan Christie, Nadir Ciftci, Saidy Janko and Jozo Simunovic.

"Subsequently, during the 2016 January transfer window, further investment has been made with the signing of Danish international Erik Sviatchenko and Turkish international Colin Kazim-Richards."

He said the board's strategy was unchanged, with the aim being to win the SPFL Premiership and qualify for the group stages of the UEFA Champions League.

Mr Bankier said: "The board considers that our self-sustaining model allows the club to look to the future with reasonable optimism.

"We sit at the heart of developments in football, both at home and in Europe, being represented by Peter Lawwell on the board of the Scottish FA, the European Club Association and on the Club Competitions Committee at UEFA. Eric Riley also serves as a director of the Scottish Professional Football League."

He said fewer home matches in the remaining moths of the financial year scheduled for meant trading performance would not be at the same level.