Inclusion Criteria:  UC or CD diagnosed within < 4 weeks using standard endoscopic, histologic or radiological criteria (ECCO Criteria). Histology report may not be available at baseline. Naïve to immunomodulators, biologics and small molecules, i.e. JAK-inhibitors Aged 18-70 years old. Is considered eligible according to tuberculosis (TB) screening criteria. Written informed consent to participate in the study  Exclusion Criteria:  A previous known diagnosis of Crohn's disease, ulcerative colitis or IBD-U, since >6 weeks before baseline Unable to provide informed consent Unable to comply with protocol requirements (e.g. for reasons including alcohol and/or recreational drug abuse) Ongoing sepsis Acute obstructive symptoms AND evidence of a fixed stricture on radiology or colonoscopy, which suggest that the patient is in need of surgery over the following year. N.B. patients with modest degrees of stricturing on imaging but no obstructive symptoms may be included according to clinician judgement Contra-indications to trial medications including a history of hepatitis B or C, tuberculosis, Cardiac failure, NYHA III-IV or hypersensitivity. Hypersenstitivity to a thiopurine agent should alert the prescriber to probable hypersensitivity to other thiopurines. History of malignancy Pregnancy Other serious medical or psychiatric illness