Offer letter

I have got an interview call two week before  from HMC  qatar.through an agency and I have attended the interview and yesterday I got the mail saying that I was selected for that job for clinical research coordinator.Can anybody please tell.me h
ow long it may take for them to send the offer letter .

It will take 4-6 weeks time to receive the offer letter, make sure don't leave your current job until they notify/ confirm to do so. 

Follow up is Must  :top:

Topic link with Hamad Medical Corporation Qatar

Thank you for the response .
Do you have any information regarding which level the does the clinical research coordinator comes.

Soonest,but forever to join them,be optimistic but not too anxious,wait patiently,and guard your current job,,,

Hi Wilsonderry - I received a pre offer from hmc two weeks back. The interview and selection was done in Nov 2018 mid . So after the pre offer was received , had asked for few revisions which they havent yet updated anything. So, in this case for revision also its been 10+ days now and the agency also has no clue to any closure timeline. Does following up the hr repeatedly sound irritating or not understanding how can this be facilitated and speed up a bit. Can you advise ?