The public should not send unsolicited parcels to British troops in Afghanistan this Christmas as they may be putting lives at risk, ministers have said.
The goodwill packages require extra helicopters and vehicles to deliver them, leaving soldiers exposed to "increased personal danger", defence minister Andrew Robathan warned.
Mr Robathan, who was updating MPs about the campaign his department is running in the lead-up to Christmas, said he wants people to show their support and affection through recognised Ministry of Defence service charities instead.
He said as part of the Government's commitment to troops deployed overseas, particularly Afghanistan, the "safe and timely delivery" of personal mail from family and friends is paramount.
In a written statement to MPs he said: "To that end, we have a policy in place which encourages the generous British public to support our troops in ways other than by sending unsolicited goodwill parcels through the mail system."
Mr Robathan said it is estimated that over Christmas there will be 19,200 unsolicited parcels sent in the mail, three times more than during a "normal" eight-week period.
He added: "In addition to the impact on personal mail, delivering unsolicited packages over the 'final mile' to forward operating bases and patrol bases puts increased pressure on essential in-theatre resources.
"Additional helicopters and road convoys are required, both of which take essential transport assets away from their primary task and place our personnel at increased personal danger."
Mr Robathan said this Christmas all personnel on operations will get a "seasonal gift box" from the charity uk4u Thanks!. Other charities which support British troops include SSAFA Forces Help , Afghan Heroes, Support our Soldiers and Operation Shoebox.
He added: "This is not an easy issue and will seem counter-intuitive to many, but I ask for your full support in directing the public towards MoD-recognised charities rather than sending unsolicited mail as a means of expressing their much valued support to our deployed personnel."