But if Louis Philippe and his ministers were determined to abstain from any intervention in Belgium, they were bound to insist that other Powers should adopt the same attitude. It was, therefore, notified to foreign governments that French policy, in the future, would be based strictly upon the principle of non-interference in the domestic affairs of other nations. It was a system to which both the great parties in England had declared their adherence, and its adoption by France might, in consequence, be expected to facilitate the establishment of cordial relations between the two countries. But the declaration of such a principle could not fail to be highly displeasing to the absolute Courts. Already movements of troops were in progress in the Rhine provinces which suggested an intention on the part of Frederick William of rendering military assistance to his brother-in-law, the King of the Netherlands. Baron Werther, the Prussian ambassador, although still without official credentials, had been instructed to remain in Paris. Molé, Louis Philippe's first Minister for Foreign Affairs, accordingly arranged to meet him at a private house, where he gave him clearly to understand that the entry of a Prussian army into the Low Countries would be regarded as an act of war directed against France. This threat, which evoked much indignation in Berlin and at Vienna, was effectual in inducing King Frederick William III. to renounce any thoughts, which he may have entertained, of reducing the Belgians to submission by force of arms.[26]