United Nations aid chief Tom Fletcher will arrive in earthquake devastated Myanmar on Friday, said U.N. Secretary-General Antonio Guterres as he appealed for more international funding and rapid, unimpeded aid access in the country.

Foreign rescue teams and supplies have arrived in Myanmar to help the impoverished country cope with a magnitude 7.7 earthquake that killed more than 1,600 people and left thousands wounded.

A U.S. team has yet to arrive in Myanmar after last week’s 7.7-magnitude earthquake, while China has already rescued six people and committed $14 million in humanitarian aid.