(a) Pursuant to the provisions of section 2401(b) of title 28 of the United States Code, a tort claim against the United States shall be forever barred unless presented in writing to the Board within two (2) years after such claim accrues.

(b) A suit may not be filed until the claim shall have been finally denied by the Board. Failure of the Board to make final disposition of the claim within six (6) months after it has been presented shall, at the option of the claimant any time thereafter, be deemed a final denial of the claim for purposes of the Act and of this part.

(c) A suit shall not be filed for a sum greater than the amount of the claim presented to the Board, except where the increased amount is based upon newly discovered evidence not reasonably discoverable at the time for presenting the claim to the Board, or upon allegation and proof of intervening facts, relating to amount of the claim.