London, Aug 21 - The Sri Lankan government has been accused of dropping a 'modern-day iron curtain' over an unfolding humanitarian crisis in its camps for Tamils displaced by its recent war against separatists.

The British Tamil Forum (BTF), a large group that says it works for Tamil self-determination through democratic means, said 300,000 Tamil civilians are confined in military-run internment camps in Sri Lanka, hidden from the glare of international witnesses.

The Sri Lankan military crushed the Liberation Tigers of Tamil Eelam (LTTE) in May to end a 20-year insurgency but its subsequent policy of confining the war displaced in refugee camps has come in for strong criticism from international aid agencies and media.

'The continuous refusal to engage with international humanitarian organisations and allow access to international monitors and free media places a modern day 'iron curtain' over a humanitarian crisis that no longer takes precedence on the international agenda and gives little hope for the Sri Lankan government's commitment towards reconciliation,' the BTF said in a statement.

'With the ongoing restrictions to aid agencies and international monitors, the true extent of the risks facing these imprisoned civilians remains vastly obscured.