Geneva - The 250,000 Tamils displaced in Sri Lanka face a deteriorating humanitarian situation as the monsoon season approaches, United Nations Secretary General Ban Ki-moon said Thursday.

"What I am concerned (about is) that conditions have not improved," Ban said, speaking about the camps where the displaced were being held.

"As we are expecting the monsoon season to come ... this can make it difficult and the situation might deteriorate. I am very concerned," Ban told reporters on the sidelines of a climate conference in Geneva.

He was scheduled to meet with a Sri Lankan minister later in the day.

Ban said displaced people - Tamils who escaped fighting between the defeated Liberation Tigers of Tamil Eelam rebels and government forces - wishing to leave the camps and live with families should be allowed to do so.

Red Cross officials have called the areas where the displaced Tamils are being held "internment camps." (dpa)