Suffolk Coastal MP Thérèse Coffey has been temporarily replaced as environment minister due to illness.
Sources said the MP had been hospitalised with an 'infection' but no further details were available and it is not clear when she might return to work.
In a statement, Number 10 said: 'David Rutley MP has been appointed temporarily whilst Thérèse Coffey MP recovers from a period of illness.'
Dr Coffey, who was appointed to Suffolk Coastal in 2010, had been the parliamentary under secretary of state for environment and rural life opportunities since July last year and was previously the deputy leader of the House of Commons.
Even during her illness she has continued to comment on the work of the environment department most recently welcoming the new clean air strategy.
It is believed her constituency work will be taken on by her office.
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