Aid agencies say a blockade on Yemen has worsened the humanitarian crisis which is gripping the country.
More than 80% of Yemen's 25 million people now need some form of aid.
Displaced by conflictUN spokesman Stephane Dujarric said: "It is imperative and urgent that humanitarian aid can reach all vulnerable people of Yemen unimpeded and through an unconditional humanitarian pause."
The pause will come into effect at 23:59 local time (20:59 GMT) on Friday.
In recent months Yemen has descended into conflicts between several different groups, although the main fight is between forces loyal to beleaguered President Abdrabbuh Mansour Hadi and Shia Zaidi rebels - or Houthis - who forced Mr Hadi to flee the capital Sanaa in February.
After rebel forces closed in on the president's southern stronghold of Aden in late March, a coalition led by Saudi Arabia responded to a request by Mr Hadi to intervene and launched air strikes on Houthi targets.
Gulf Arab states have accused Iran of backing the Houthis financially and militarily, though Iran has denied this.
On Tuesday, the UN announced that at least 1,528 civilians were among the 3,000 dead.
Another one million civilians have been displaced by the conflict.
Charities say a lack of fuel in Yemen is making it difficult to reach those in need and to provide adequate care in hospitals.
The coalition allowed a five-day humanitarian ceasefire in May, but much of the aid promised to those in need has failed to materialise.
Yemen is strategically important because it sits on the Bab al-Mandab strait, a narrow waterway linking the Red Sea with the Gulf of Aden, through which much of the world's oil shipments pass