It is a separate phase.
Cut from RAC:
3.1 Sequence of play
The sequence of play in a turn is:
A. REINFORCEMENT STAGE
B. LENDING RESOURCES STAGE
C. INITIATIVE STAGE
D. ACTION STAGE
Repeat D1 through D3 until the action stage ends.
D1 Determine weather
D2 First side’s impulse
Every major power on the first side performs these steps:
D2.1 Declare war
D2.2 Choose action
Choose either a Pass, a Naval, an Air, a Land or a Combined action.
D2.3 Perform actions
The major powers that didn’t pass perform these steps in this order (their action choice will limit
what they can do ~ see action limits table):
(a) Port attacks
(b) Naval air missions
(c) Naval movement
(d) Phasing player’s naval combat
(e) Non-phasing player’s naval combat
(f) Strategic bombardment
(g) Carpet bombing (option 32)
(h) Ground strike missions
(i) Rail movement
(j) Land movement
(k) Air transport
(l) Debark land units at sea
(o) Land combat
(p) Air rebases
D2.4 End of action
Roll to end the action stage. If it doesn’t end, advance the impulse marker the number of spaces
shown on the weather chart for the current weather roll. If it ends, move on to stage E.
D3 Second side’s impulse
If the action stage didn’t end, repeat the steps in D2 for the second side. If the action stage doesn’t
end after the second side’s impulse, go back to D1.
Have a bit more patience with newbies. Of course some of them act dumb -- they're often students, for heaven's sake. - Terry Pratchett