SCHEDULE 13D

CUSIP Number(s):

95805V108

1

Name of reporting person

Rio Tinto plc

2

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

3

SEC use only

4

Source of funds (See Instructions)

WC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

6

Citizenship or place of organization

UNITED KINGDOM

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 19,004,925.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 19,004,925.00

11

Aggregate amount beneficially owned by each reporting person

19,004,925.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

13

Percent of class represented by amount in Row (11)

8.42 %

14

Type of Reporting Person (See Instructions)

HC, CO

Comment for Type of Reporting Person:

For rows 8, 10, 11 and 13, see Item 5. For row 13, the calculation is based on 225,628,684 common shares, without par value (the "Shares"), being the number of Shares outstanding as of March 25, 2026, as disclosed in the Company's Annual Information Form for the year ended December 31, 2025.

SCHEDULE 13D

CUSIP Number(s):

95805V108

1

Name of reporting person

Rio Tinto Canada Inc.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)

(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

Checkbox not checked

6

Citizenship or place of organization

CANADA (FEDERAL LEVEL)

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 19,004,925.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 19,004,925.00

11

Aggregate amount beneficially owned by each reporting person

19,004,925.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

Checkbox not checked

13

Percent of class represented by amount in Row (11)

8.42 %

14

Type of Reporting Person (See Instructions)

CO

Comment for Type of Reporting Person:

For rows 8, 10, 11 and 13, see Item 5. For row 13, the calculation is based on 225,628,684 common shares, without par value (the "Shares"), being the number of Shares outstanding as of March 25, 2026, as disclosed in the Company's Annual Information Form for the year ended December 31,2025.

SCHEDULE 13D

Item 1.

Security and Issuer

(a)

Title of Class of Securities:

Common Shares, without par value

(b)

Name of Issuer:

Western Copper and Gold Corporation

(c)

Address of Issuer's Principal Executive Offices:

Suite 907 - 1030 West Georgia Street, Vancouver, BRITISH COLUMBIA, CANADA , V6E 2Y3.

Item 1 Comment:

This Amendment No. 4 ("Amendment No. 4") relates to the Statement on Schedule 13D (this "Schedule 13D") filed on April 1, 2026 by Rio Tinto plc, a public limited company incorporated under the laws of England and Wales ("Rio Tinto"), and Rio Tinto Canada Inc., a corporation incorporated under the laws of Canada ("RTCI" and, together with Rio Tinto, the "Rio Tinto Companies"). Except as otherwise provided herein, each item of the Original Schedule 13D remains unchanged. Explanatory Note: This Amendment No. 4 is being filed to reflect a passive decrease of greater than one percent (1%) in the percentage of the Company's Common Shares owned beneficially by the Reporting Persons based on the Company's disclosure of the number of Common Shares outstanding.

Item 4.

Purpose of Transaction

Item 4 of the Original Schedule 13D is hereby amended and supplemented by adding the following information: The Company discloses the number of its issued and outstanding Common Shares on a quarterly basis. On March 26, 2026, the Company filed its Form 40-F with the Securities and Exchange Commission including as an Exhibit the Company's Annual Information Form for the year ended Dember 31, 2025. The Annual Information Form disclosed on page 26 that "[a]s of March 25, 2026, the Company had 225,628,684 Common Shares issued and outstanding."

Item 5.

Interest in Securities of the Issuer

(c)

Item 5 of the Original Schedule 13D is hereby amended and supplemented by adding the following information: The information set forth in Item 4 of this Amendment No. 4 is incorporated by reference in its entirety into this Item 5. There were no other transactions by the reporting persons that were effected during the past 60 days.

Item 7.

Material to be Filed as Exhibits.

A Joint Filing Agreement between Rio Tinto plc and Rio Tinto Canada Inc., dated November 23, 2022.* B Subscription Agreement between Western Copper and Gold Corporation and Rio Tinto Canada Inc. dated May 14, 2021.* C Investor Rights Agreement between Western Copper and Gold Corporation and Rio Tinto Canada Inc. dated May 28, 2021.* D Extension letter dated November 22, 2022, from Rio Tinto Canada Inc. to Western Copper and Gold Corporation.* E Subscription Agreement, dated November 27, 2023, between Western Copper and Gold Corporation and Rio Tinto Canada Inc. F Amended and Restated Investor Rights Agreement dated November 27, 2023, between Western Copper and Gold Corporation and Rio Tinto Canada Inc.* G Form of Second Amended and Restated Investor Rights Agreement dated June 13, 2025, between Western Copper and Gold Corporation and Rio Tinto Canada Inc.* * Previously filed.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Rio Tinto plc

Signature:	/s/Andy Hodges
Name/Title:	Andy Hodges, Company Secretary
Date:	04/01/2026

Rio Tinto Canada Inc.

Signature:	/s/Julie Parent
Name/Title:	Julie Parent, Director
Date:	04/01/2026