Do postgres use implicit transaction in UPDATE ... RETURNING queries?

[Debraj Manna <subharaj.manna@xxxxxxxxx>]

Can someone let me know if Postgres 15 uses implicit transactions for UPDATE...RETURNING queries?

For example, is there any differences between the two queries

BEGIN;
UPDATE counter
SET value = value + 1
RETURNING value;
COMMIT;

and

UPDATE counter
SET value = value + 1
RETURNING value;

Table is like below

CREATE TABLE IF NOT EXISTS counter
(
    value      bigint PRIMARY KEY NOT NULL DEFAULT 0,
    updated_at TIMESTAMPTZ        NOT NULL DEFAULT CURRENT_TIMESTAMP
);