WASHINGTON, Oct 4 (Reuters) - It is critical that United Nations officials expelled from Ethiopia be allowed to return to the country, the U.S. State Department said on Monday. State Department spokesman Ned Price made the comment during a regular briefing, after Ethiopia last week said it was expelling seven U.N. officials days after the world body"s aid chief warned a government blockade of aid had likely forced hundreds of thousands of people in the northern region of Tigray into famine. read more