回复3楼:
英国是党魁才有资格当首相，辞去党魁，就相当于辞去首相，除非，他可以再次当选为党魁。

:
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这是党规：党首“选”作首相。英国宪政惯例：辞去党首，临时继续担任首相没问题，以前多次出现这种情形，例如特雷莎梅接替卡梅伦，和约翰逊第一次上台接替梅时，都是如此做法。今天的情形，你可以参考bbc的报道：
https://www.bbc.co.uk/news/live/uk-politics-62072419
：
Boris Johnson is to resign as Conservative leader today, the BBC is told, following further ministerial resignations this morning
.
But he will continue to serve as prime minister until the autumn to allow a Tory leadership contest to take place
…