diff --git a/phpBB/docs/INSTALL.html b/phpBB/docs/INSTALL.html
index c03577cd44..2552d3499b 100644
--- a/phpBB/docs/INSTALL.html
+++ b/phpBB/docs/INSTALL.html
@@ -147,7 +147,7 @@
 			<li>Oracle</li>
 		</ul>
 		</li>
-		<li><strong>PHP 7.1.0+</strong> with support for the database you intend to use.</li>
+		<li><strong>PHP 7.1.0+</strong> but less than <strong>PHP 7.3</strong> with support for the database you intend to use.</li>
 		<li>The following PHP modules are required:
 		<ul>
 			<li>json</li>
diff --git a/phpBB/install/app.php b/phpBB/install/app.php
index 9d04ec2156..ad71ee369f 100644
--- a/phpBB/install/app.php
+++ b/phpBB/install/app.php
@@ -20,9 +20,9 @@ define('PHPBB_ENVIRONMENT', 'production');
 $phpbb_root_path = '../';
 $phpEx = substr(strrchr(__FILE__, '.'), 1);
 
-if (version_compare(PHP_VERSION, '7.1') < 0)
+if (version_compare(PHP_VERSION, '7.1', '<') || version_compare(PHP_VERSION, '7.3-dev', '>='))
 {
-	die('You are running an unsupported PHP version. Please upgrade to PHP 7.1.0 or higher before trying to install or update to phpBB 3.3');
+	die('You are running an unsupported PHP version. Please upgrade to PHP equal to or greater than 7.1.0 but less than 7.3-dev in order to install or update to phpBB 3.2');
 }
 
 $startup_new_path = $phpbb_root_path . 'install/update/update/new/install/startup.' . $phpEx;