Launch of Consent Solicitation

(Regulation S Notes: ISIN USG91237AB60, Common Code G91237AB6; Rule 144A Notes: ISIN US899415AG89, Common Code 899415AG8)

(together, the "Notes")

25 March 2026 - Further to recent announcements regarding the proposed refinancing transaction (the "Refinancing Transaction"), Tullow Oil plc ("Tullow") is pleased to announce that it has today launched a solicitation (the "Consent Solicitation") for the formal consents (the "Consents") from the holders of the Notes ("Holders") required in connection with the implementation of the Transaction.

As more fully described in the Consent Solicitation Statement, the Consent Solicitation and the Refinancing Transaction are part of a series of transactions contemplated by a lock-up agreement (the "Lock-Up Agreement"). The Refinancing Transaction was announced on 20 February 2026 with the support of Holders holding c.66% of the aggregate principal amount of the Notes and Glencore (together, the "Consenting Creditors"). On 26 February 2026, it was announced that Holders holding over 90% of the aggregate principal amount of the Notes had acceded to the Lock-Up Agreement and, as of the date hereof, Holders holding 99.48% of the aggregate principal amount of the Notes have acceded to the Lock-up Agreement and are expected to approve the Amendments (as defined below).

The Consent Solicitation seeks consent from the Holders to approve (i) certain amendments (the "Proposed Indenture Amendments") to the indenture dated as of May 17, 2021, as amended, supplemented or waived from time to time providing for the issuance of the Notes (the "Indenture"), (ii) certain amendments to the intercreditor agreement and (iii) the release of the existing Notes and issuance of New Notes (as defined in the Consent Solicitation Statement) to all Holders (regardless of whether they participate in the Consent Solicitation) as a new series of notes under the amended and restated Indenture (together with (i) and (ii), the "Amendments"), in each case as set out in the consent solicitation statement dated 25 March 2026 (the "Consent Solicitation Statement"). The Consent Solicitation is being made solely on the terms and subject to the conditions set forth in the Consent Solicitation Statement.

Adoption of the Amendments requires receipt of consents from Holders representing no less than 90% in principal amount of the Notes outstanding (the "Required Consents"). A Consent may be validly revoked by a Holder at any time prior to, but not on or after, the Effective Time (as defined below) and will automatically terminate and not be effective if the Required Consents for the Notes are not obtained on or prior to the Expiration Time (as defined below).

Tullow expects that, as soon as practicable following the receipt of the Required Consents, it will give notice to GLAS Trust Company LLC as trustee under the Indenture (the "Existing Notes Trustee") that the Required Consents have been received (at such time, the "Effective Time"), and Tullow, the Existing Notes Trustee and the other parties thereto, as applicable, will execute (i) a supplemental indenture to amend the Indenture to permit the redemption of the existing Notes on a pro rata basis, (ii) a supplemental indenture to amend the Indenture to reflect the other Proposed Indenture Amendments and (iii) subject to the required consents being received from required other parties to the Intercreditor Agreement, an amended and restated intercreditor agreement. Holders should also note that the Effective Time may fall prior to the Expiration Time (as defined below), and, if so, Holders would not be given prior notice of such Effective Time.

The Consent Solicitation will expire at 11:59 P.M. (New York City time), 21 April 2026, unless extended by Tullow (the "Expiration Time"). Tullow may, in its sole discretion, terminate, extend or amend the Consent Solicitation at any time as described in the Consent Solicitation Statement.

Copies of the consent solicitation statement pursuant to which the Consent Solicitation is being effectuated may be, together with any other documentation Tullow may publish from time to time, obtained from the information and tabulation agent Kroll Issuer Services Limited via the Transaction Website at https://deals.is.kroll.com/tullow.

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