asked Her Majesty's Government:

Whether they are obliged to consult the law officers of the Crown about the compatibility with international law of any proposed use of force by the Armed Forces before engaging or participating in any act of war or military intervention. [HL556]

The circumstances in which it will normally be appropriate to consult the law officers are set out in paragraph 6.22 of the Ministerial Code. The Government take all appropriate steps to ensure that any overseas military operations are commenced and conducted in compliance with all relevant obligations under international law, which will include taking legal advice as necessary. This will generally include seeking legal clearance from the law officers before any decision is taken to commence military action.