I did this crack at it a while ago - its the OEF_ACU, but is pretty darn close to the MTP (which has a more brush-stroke effect and slightly different tones).

The base colours are:
Vallejo 70987 Medium Grey (with Buff Highlights)
Vallejo 70921 English Uniform
Foundry Phlegm Green 28c (Light)
Camoflage Detail colours are:
Vallejo 70922 Uniform Green
Foundry Boneyard Light 9C
Vallejo 70872 Chocolate Brown
The whole thing was then dulled down with a glaze of Vallejo Buff/Medium grey mix.
The US pattern has broad 'overspray' stripes as the underlying plan, wheras the Brit version seems to be more sectional - looks like buff and mid-brown over the pea/olive tint. Had a good look at this as the troops coming in and out of the local airbase are covered in the stuff now.
The base colours are:
Vallejo 70987 Medium Grey (with Buff Highlights)
Vallejo 70921 English Uniform
Foundry Phlegm Green 28c (Light)
Camoflage Detail colours are:
Vallejo 70922 Uniform Green
Foundry Boneyard Light 9C
Vallejo 70872 Chocolate Brown
The whole thing was then dulled down with a glaze of Vallejo Buff/Medium grey mix.