The embassy recently requested Bangladesh government to take the necessary steps towards this end.

The embassy officials on March 2 sat in a meeting with foreign ministry officials to discuss the DPO and to launch the process for its introduction, ministry sources said. They also informed the National Board of Revenue (NBR) about the move, requesting the board to bring in the changes in customs procedure required to implement it.

A foreign ministry official said they are not yet clear about the proposed DPO, which is a completely new subject for them.

"We have not been informed what purpose such a DPO would serve, as the embassy already enjoys uninterrupted mail dispatch and receiving facilities under the Vienna Convention on Diplomatic Relation," the official at the foreign ministry's Asia Pacific and America Wing said.

Sources said the US State Department plans to set up DPOs at all its overseas missions. A letter of the US embassy to the NBR said the plan is still in its embryonic stage and currently there are only five DPOs in operation across the world.

The DPO in Dhaka would be established under the second round of the plan that also includes DPOs in Dubai, India, Nepal, Syria and Thailand, sources said. The US postal service has already completed the groundwork.

According to sources, the major difference between the current and the proposed system is the change of the mail carrier. "Under the new system, all diplomatic mails to and from the US embassy will be under the control of and carried by the US postal service, along with other US mail," a foreign ministry source said.

He said the diplomatic mail would be carried in yellow bags bearing the logo of US postal service and with a tag identifying its diplomatic content. Currently the US embassy mail is shipped separately in diplomatic bags bearing State Department logo by British Airways.

Such a DPO might cause confusion and also encourage other embassies for going for similar facilities, remarked an NBR high official.