Norway's troubled campaign came to a shuddering halt with a 3-1 loss to Japan in the last 16 on Saturday after internal disputes and disappointing results on the field.

"All in all, it is a championship that we are disappointed with and for which we must all take responsibility," Klaveness told Norwegian broadcaster NRK on Wednesday.

"I would like to apologise to all our supporters who were hoping for something even more."

Klaveness acknowledged that Norway had enjoyed some luck on their way to the last 16 and expressed concern that recent overall performances had not been up to standard.

Although the opening 1-0 loss to co-hosts New Zealand was nowhere near as bad as their 8-0 thrashing by England in last year's Euros it was still embarrassing, effectively establishing the groundwork for yet another disheartening campaign.

"We have to realise that in three of the last four championships, we have performed lower than we expected," Klaveness added.

"Where are we two years from now, where are we four years from now and are we falling behind? That's what we've been doing in recent years and that's not what we're going to do. We're going on the offensive."

Klaveness said the objective was to complete an assessment of the issues by the end of August, covering the federation, players, coaches, and support staff.