The United Kingdom and <a href="https://en.wikipedia.org/wiki/Second_Polish_Republic" id="mwsQ" rel="mw:WikiLink" title="Second Polish Republic">Poland</a> form a <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Anglo-Polish_military_alliance" id="mwsg" rel="mw:WikiLink" title="Anglo-Polish military alliance">military alliance</a> in which the UK promises to defend Poland in case of invasion by a foreign power.