diff --git a/README.markdown b/README.markdown
index fc11302..3c2da81 100644
--- a/README.markdown
+++ b/README.markdown
@@ -261,7 +261,9 @@ transaction.merchant_authorize # this will charge the card without user interact
 XML Transactions
 ================
 
-XML API is [deprecated](https://mailchi.mp/datatrans/basic-authdynamic-sign_reminder) by Datatrans. After June 3rd, 2024 all merchants will have to use JSON API.
+> [!IMPORTANT]
+>
+> Datatrans will stop supporting the XML API on June 3rd, 2024. The support in this gem will be removed in the next major release. Please use the [JSON API](#json-transactions) instead.
 
 If you have already a credit card alias or an authorized transaction you can
 use the convenient XML methods to process payments.
diff --git a/lib/datatrans/config.rb b/lib/datatrans/config.rb
index 7453789..76164d2 100644
--- a/lib/datatrans/config.rb
+++ b/lib/datatrans/config.rb
@@ -43,15 +43,22 @@ def url(what, options = {})
       case what
       when :web_authorize_url
         warn "DEPRECATION WARNING: Support for the payment page is deprecated and will be removed in the next major version. Please use the JSON API instead."
+
         subdomain = SUBDOMAINS[:payment_page]
         path = "/upp/jsp/upStart.jsp"
       when :xml_authorize_url
+        warn "DEPRECATION WARNING: Support for the XML API is deprecated and will be removed in the next major version. Please use the JSON API instead."
+
         subdomain = SUBDOMAINS[:server_to_server_api]
         path = "/upp/jsp/XML_authorize.jsp"
       when :xml_settlement_url
+        warn "DEPRECATION WARNING: Support for the XML API is deprecated and will be removed in the next major version. Please use the JSON API instead."
+
         subdomain = SUBDOMAINS[:server_to_server_api]
         path = "/upp/jsp/XML_processor.jsp"
       when :xml_status_url
+        warn "DEPRECATION WARNING: Support for the XML API is deprecated and will be removed in the next major version. Please use the JSON API instead."
+
         subdomain = SUBDOMAINS[:server_to_server_api]
         path = "/upp/jsp/XML_status.jsp"
       when :init_transaction
diff --git a/lib/datatrans/xml/transaction.rb b/lib/datatrans/xml/transaction.rb
index 36c838e..d866142 100644
--- a/lib/datatrans/xml/transaction.rb
+++ b/lib/datatrans/xml/transaction.rb
@@ -6,6 +6,8 @@ class Transaction
     attr_reader :response, :params, :datatrans
 
     def initialize(datatrans, params)
+      warn "DEPRECATION WARNING: Support for the XML API is deprecated and will be removed in the next major version. Please use the JSON API instead."
+
       @datatrans = datatrans
       @params = params.symbolize_keys
     end
diff --git a/lib/datatrans/xml/transaction/request.rb b/lib/datatrans/xml/transaction/request.rb
index f8b9875..a9a1d37 100644
--- a/lib/datatrans/xml/transaction/request.rb
+++ b/lib/datatrans/xml/transaction/request.rb
@@ -13,6 +13,8 @@ def post(url, options = {})
     end
 
     def initialize(datatrans, params)
+      warn "DEPRECATION WARNING: Support for the XML API is deprecated and will be removed in the next major version. Please use the JSON API instead."
+
       @datatrans = datatrans
       @params = params
     end
diff --git a/lib/datatrans/xml/transaction/response.rb b/lib/datatrans/xml/transaction/response.rb
index e313b07..71268d3 100644
--- a/lib/datatrans/xml/transaction/response.rb
+++ b/lib/datatrans/xml/transaction/response.rb
@@ -3,6 +3,8 @@ class Response
     attr_reader :params, :datatrans
 
     def initialize(datatrans, params)
+      warn "DEPRECATION WARNING: Support for the XML API is deprecated and will be removed in the next major version. Please use the JSON API instead."
+
       @datatrans = datatrans
       @params = params
     end