No one immediately claimed responsibility for Wednesday's attack, but both Taliban and Islamic State group are active in eastern Afghanistan.
Trump had said the US was walking away from negotiations after nearly a year of grinding diplomatic efforts to strike a deal that could pave the way for an American withdrawal from Afghanistan.
President Maithripala Sirisena has been extending the emergency on the 22nd of each month since the April 21 attacks on three hotels and three churches.
The Islamic State affiliate appeared in Afghanistan shortly after the group's core fighters swept across Syria and Iraq in 2014 in around a third of both countries.
Gunmen on motorcycles opened fire on police in a residential area, killing two, then the bomber struck at the entrance to the hospital, killing another four police and three civilians.
No one took responsibility for the attack, but both the Taliban and the Islamic State affiliate have a strong presence in eastern Afghanistan.
A suicide bombing outside a voter and ID registration centre in Kabul killed at least 57 people, and injured 112 people.
The assault underscores growing concerns about security in the lead-up to legislative elections scheduled for October 20, which are seen as a test-run for next year's presidential poll.
The attackers targeted the convoy of security forces on the Sariab road in the provincial capital Quetta, they said.
The Islamic State group issued a claim of responsibility, saying in an online statement that it had carried out the attack as the Egyptian army was preparing an assault on IS positions in Sinai.
Iran on Saturday condemned a suicide bombing near Islam's holiest site in Mecca and offered Saudi Arabia its assistance in tackling terrorism despite their severed ties.
There were mixed reports, with some local news agencies reporting there was a single shooter inside the Tehran complex and others saying there were three men.