“In my opinion the courts of this jurisdiction should be very slow to make orders that directly conflict with pre-existing orders in any friendly foreign state. The principle of comity requires no less.” 27. And further, in Mercredi v Chaffe[2011] 2 FLR 515 at 527: “…. as a matter of comity and the collaboration of courts within the European Union the London judge had an obligation to support the proper conclusions of the French court or, at the least, not to enter into a litigation strategy to undermine the order… [67] One the one hand it can be said that the general rule must be that jurisdiction is established in the State of the habitual residence of the child at the time the court is seised. Once seised that court retains jurisdiction even if the child changes habitual residence during the course of the proceedings. This is the principle of petuatio fori. It is a practical rule to prevent one party from aborting proceedings by a tactical move during their course. Thus it can be argued that the issue of Children Act proceedings fixed jurisdiction in London until the termination of the proceedings.”