The Care Quality Commission told North Middlesex University Hospital in June to boost its staffing and performance.
Seventeen more senior doctors have since joined and waiting times have been cut by 25%, the hospital said.
The GMC had warned that unless the hospital's recruitment target was met, it would remove 26 junior doctors in training, forcing the unit to shut.
In a statement, the regulator said: "The CQC has been working with the trust to make sure the improvements asked for in the Warning Notice have been met.
"CQC will be inspecting North Middlesex again in the next few weeks and a report will be published in due course."
The hospital was given until Friday to meet the recommendations.
The CQC issued a warning notice on 6 June saying the hospital should "significantly improve" the treatment of patients attending the emergency department.
The GMC and Health Education England also set out a series of requirements the hospital had to meet, failing which postgraduate training would not be allowed to continue.
Dr Turan Huseyin, the new clinical director appointed to bring in the changes, said the hospital now had an in-house matron and a new medical director to lead the 200 staff, in addition to several senior doctors on loan.
He told BBC Radio London: "At the time there were only seven consultants, we now have 15 on the shop floor, there were only seven middle grade and sub-consultant grades, we now have 13 on the shop floor.
"We now have the right number of staff that is making it a lot safer and that is helping with morale."
Junior doctors said they now felt "well supported", he said.
The four-hour waiting time target to be seen at A&E was met 65% of the time by April and went up to 90% in August, which is close to the national target of 95%, the hospital said.
A hospital warned its A&E unit could be closed amid safety fears has hired more doctors since a damning inspection.