Generate a phone link with an aria-label for accessibility.

functions.php

<?php
/**
 * Generate a phone link with an aria-label for accessibility.
 *
 * @link https://link.from.pw/3HElEp9
 *
 * @param string $phone The phone number to format.
 * @param string $class Optional. The CSS class name to add to the link.
 *
 * @return string The formatted telephone link.
 */
function kanuka_accessible_phone_link( $phone, $class = '' ) {

	// Rough check for a valid phone number.
	if ( ! preg_match( '/^[0-9+\-()\s]+$/', $phone ) ) {
		return $phone;
	}

	// Remove spaces from phone number.
	$tel = preg_replace( '/\s+/', '', $phone );

	// Remove non-numeric characters except the plus sign and spaces.
	$aria_label = preg_replace( '/[^0-9+\s]/', '', $phone );

	// Add full stop at the end of each group of characters.
	$aria_label = str_replace( ' ', '. ', $aria_label ) . '.';

	// Remove all spaces.
	$aria_label = str_replace( ' ', '', $aria_label );

	// Add a space between each character.
	$aria_label = implode( ' ', str_split( $aria_label ) );

	// Remove spaces before full stops.
	$aria_label = str_replace( ' .', '.', $aria_label );

	// Generate the link.
	$link = '<a href="tel:' . $tel . '" aria-label="' . $aria_label . '"';

	// Add the class attribute if a class name was provided.
	if ( ! empty( $class ) ) {
		$link .= ' class="' . $class . '"';
	}

	$link .= '>' . $phone . '</a>';

	// Return the link
	return $link;
}