He will take part in a conference with the United Nations and the ASEAN group of countries in Rangoon.

The conference comes after UN secretary general Ban Ki-moon revealed that senior Burmese general Than Shwe had agreed to allow all aid workers into the country "regardless of nationality".

On Saturday, Mr Alexander met with Mr Ban and warned that the Burmese authorities must put their words into actions and help the victims of Cyclone Nargis.

Burma has been left crippled after the cyclone struck on May 2. Nearly 78,000 people have been confirmed dead, with a further 56,000 missing.

The Burmese authorities have come under concerted international pressure to allow more relief and aid workers into the country to help speed up the recovery process.

Mr Alexander said: "While we are encouraged by the work of the UN secretary general to secure the commitment of the Burmese authorities to improve access, the real and most immediate focus of the meeting in Rangoon must be turning the words of the Burmese regime into action by the Burmese regime. It will be vital that UN and ASEAN efforts are kick-started to deliver."

He said the Department for International Development would be sending 11 flights carrying much-needed materials for families that have lost their homes in this devastating cyclone in the next few weeks.

Mr Alexander explained: "This will help provide additional shelter for up to 250,000 people in the Irrawaddy Delta and around Rangoon."

A spokeswoman from the United Nations Office for the Co-ordination of Humanitarian Affairs said it was too early to be sure how much access would be achieved.