UPDATE 1-UK finance minister Sunak resigns

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LONDON, July 5 (Reuters) - British finance minister Rishi Sunak resigned on Tuesday, saying he had reluctantly come to the conclusion that "we cannot continue like this".

"The public rightly expect government to be conducted properly, competently and seriously. I recognise this may be my last ministerial job, but I believe these standards are worth fighting for and that is why I am resigning," he said on Twitter.

In his resignation letter to the prime minister, also posted on his Twitter account, Sunak pointed to "immense challenges" that Britain was facing, adding that the people were "ready to hear the truth".

"In preparation for our proposed joint speech on the economy next week, it has become clear to me that our approaches are fundamentally different," Sunak said.

His resignation came minutes after Health Secretary stepped down after he had lost confidence in Johnson's ability to govern in the national interest.

(Reporting by Kate Holton; editing by William James)