asked the Secretary of State for Foreign Affairs what boundaries were at any time agreed to by any British Government for postwar Poland, and to what extent the Oder and Neisse formed part of these boundaries.

I presume that my hon. Friend's Question refers to the Western frontiers of Poland. Here the position is that the three Heads of Governments agreed at the Potsdam Conference that, pending the final delimitation of this frontier of Poland at the Peace settlement, the following territories should be under the administration of the Polish State: the former German territories east of a line running from the Baltic Sea immediately west of Swinemunde and thence along the Oder River to the Confluence of the Western Neisse River and along the Western Neisse to the Czechoslovak frontier, including that portion of East Prussia not placed under the administration of the U.S.S.R. in accordance with the understanding reached at Potsdam and including the area of the former Free City of Danzig.

Was any document suppressed by Mr. Mikolajczyk?

I assume that my hon. Friend refers to a letter written by Sir Alexander Cadogan in this context. As has already been stated in this House, that letter forms part of a long diplomatic correspondence leading up to the Potsdam Agreement and was superseded by that Agreement.