diff --git a/CHANGELOG.md b/CHANGELOG.md
index 26483c2..cc5ec4b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,7 +7,12 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 
-## [Unreleased]
+## [2.4.0] - Unreleased
+
+### Changed
+
+- Allow `psr/http-message` v2 in addition to v1
+- Deprecate `Http\Client\HttpClient`, use [PSR-18](https://www.php-fig.org/psr/psr-18/) instead
 
 ## [2.3.0] - 2022-02-21
 
diff --git a/composer.json b/composer.json
index c169089..7391770 100644
--- a/composer.json
+++ b/composer.json
@@ -22,7 +22,7 @@
         "php": "^7.1 || ^8.0",
         "php-http/promise": "^1.1",
         "psr/http-client": "^1.0",
-        "psr/http-message": "^1.0"
+        "psr/http-message": "^1.0 || ^2.0"
     },
     "require-dev": {
         "friends-of-phpspec/phpspec-code-coverage": "^4.1 || ^5.0 || ^6.0",
diff --git a/spec/Exception/HttpExceptionSpec.php b/spec/Exception/HttpExceptionSpec.php
index 3658f56..20eb58e 100644
--- a/spec/Exception/HttpExceptionSpec.php
+++ b/spec/Exception/HttpExceptionSpec.php
@@ -10,6 +10,8 @@ class HttpExceptionSpec extends ObjectBehavior
 {
     function let(RequestInterface $request, ResponseInterface $response)
     {
+        $response->getStatusCode()->willReturn(500);
+
         $this->beConstructedWith('message', $request, $response);
     }
 
diff --git a/src/HttpClient.php b/src/HttpClient.php
index 4442bd0..22b94aa 100644
--- a/src/HttpClient.php
+++ b/src/HttpClient.php
@@ -9,6 +9,8 @@
  *
  * Provide the Httplug HttpClient interface for BC.
  * You should typehint Psr\Http\Client\ClientInterface in new code
+ *
+ * @deprecated since version 2.4, use Psr\Http\Client\ClientInterface instead; see https://www.php-fig.org/psr/psr-18/
  */
 interface HttpClient extends ClientInterface
 {