In the United Kingdom, the Speaker of the House of Commons does not merely remove themselves from their party caucus — they cease all partisan activity. After being appointed to the post, the U.K. Speaker runs as an independent candidate in subsequent elections — and the major parties typically agree to not run candidates against them.
source https://www.cbc.ca/news/politics/greg-fergus-speaker-conservatives-1.7211706?cmp=rss