Under FIDIC Red Book 1999, Sub-Clause 17.3 defines Employer’s Risks, which include war, hostilities, rebellion, revolution, insurrection, or military/usurped power. The scenario clearly falls within “insurrection,” making it an Employer’s Risk. Consequently, under Sub-Clause 17.4, the Contractor is entitled to both Extension of Time (EOT) and Cost if such risks affect execution of the Works.

At this stage, the Engineer must acknowledge that the event qualifies as an Employer’s Risk and that entitlement in principle exists. However, the exact quantum of delay and Cost cannot yet be determined because the situation is ongoing. FIDIC practice allows for such claims to be assessed after the effects are known. Importantly, the Contractor has already provided notice, satisfying Sub-Clause 20.1 requirements.

Option B is incorrect because entitlement is not conditional upon the end of the event; only quantification is deferred. Option C is wrong because foreseeability does not negate Employer’s Risks explicitly listed in Sub-Clause 17.3. Option D misapplies Sub-Clause 2.1, which relates to access to the Site, not political violence or insurrection.

Therefore, Option A correctly reflects FIDIC principles: recognition of entitlement with later assessment of time and cost.