diff --git a/utils/proxy-liteserver.cpp b/utils/proxy-liteserver.cpp
index 66161fc45..a9baa7595 100644
--- a/utils/proxy-liteserver.cpp
+++ b/utils/proxy-liteserver.cpp
@@ -43,8 +43,12 @@
 #if TD_DARWIN || TD_LINUX
 #include <unistd.h>
 #endif
+#include "td/utils/overloaded.h"
+
 #include <iostream>
 #include <map>
+#include <auto/tl/lite_api.hpp>
+#include "td/utils/tl_storers.h"
 
 using namespace ton;
 
@@ -252,26 +256,93 @@ class ProxyLiteserver : public td::actor::Actor {
   }
 
   void receive_query(td::BufferSlice data, td::Promise<td::BufferSlice> promise) {
+    // Like in ValidatorManagerImpl::run_ext_query
+    auto F = fetch_tl_object<lite_api::liteServer_query>(data, true);
+    if (F.is_ok()) {
+      data = std::move(F.move_as_ok()->data_);
+    } else {
+      auto G = fetch_tl_prefix<lite_api::liteServer_queryPrefix>(data, true);
+      if (G.is_error()) {
+        promise.set_error(G.move_as_error());
+        return;
+      }
+    }
+
+    tl_object_ptr<lite_api::liteServer_waitMasterchainSeqno> wait_mc_seqno_obj;
+    auto E = fetch_tl_prefix<lite_api::liteServer_waitMasterchainSeqno>(data, true);
+    if (E.is_ok()) {
+      wait_mc_seqno_obj = E.move_as_ok();
+    }
     liteclient::QueryInfo query_info = liteclient::get_query_info(data);
     ++ls_stats_[query_info.query_id];
-    promise = [promise = std::move(promise), query_info, timer = td::Timer()](td::Result<td::BufferSlice> R) mutable {
+    promise = [promise = std::move(promise), query_info, timer = td::Timer(),
+               wait_mc_seqno =
+                   (wait_mc_seqno_obj ? wait_mc_seqno_obj->seqno_ : 0)](td::Result<td::BufferSlice> R) mutable {
       if (R.is_ok()) {
-        LOG(INFO) << "Query " << query_info.to_str() << ": OK, time=" << timer.elapsed()
-                  << ", response_size=" << R.ok().size();
+        LOG(INFO) << "Query " << query_info.to_str()
+                  << (wait_mc_seqno ? PSTRING() << " (wait seqno " << wait_mc_seqno << ")" : "")
+                  << ": OK, time=" << timer.elapsed() << ", response_size=" << R.ok().size();
         promise.set_value(R.move_as_ok());
         return;
       }
-      LOG(INFO) << "Query " << query_info.to_str() << ": " << R.error();
+      LOG(INFO) << "Query " << query_info.to_str()
+                << (wait_mc_seqno ? PSTRING() << " (wait seqno " << wait_mc_seqno << ")" : "") << ": " << R.error();
       promise.set_value(create_serialize_tl_object<lite_api::liteServer_error>(
           R.error().code(), "Gateway error: " + R.error().message().str()));
     };
-    TRY_RESULT_PROMISE(promise, server_idx, select_server(query_info));
 
+    TRY_RESULT_PROMISE(promise, server_idx, select_server(query_info));
     Server& server = servers_[server_idx];
-    LOG(INFO) << "Sending query " << query_info.to_str() << ", size=" << data.size() << ", to server #" << server_idx
-              << " (" << server.config.addr.get_ip_str() << ":" << server.config.addr.get_port() << ")";
+    LOG(INFO) << "Sending query " << query_info.to_str()
+              << (wait_mc_seqno_obj ? PSTRING() << " (wait seqno " << wait_mc_seqno_obj->seqno_ << ")" : "")
+              << ", size=" << data.size() << ", to server #" << server_idx << " (" << server.config.addr.get_ip_str()
+              << ":" << server.config.addr.get_port() << ")";
+
+    BlockSeqno wait_mc_seqno = wait_mc_seqno_obj ? wait_mc_seqno_obj->seqno_ : 0;
+    wait_mc_seqno = std::max(wait_mc_seqno, last_known_masterchain_seqno_);
+    if (server.last_known_masterchain_seqno < wait_mc_seqno) {
+      int timeout_ms = wait_mc_seqno_obj ? wait_mc_seqno_obj->timeout_ms_ : 8000;
+      data = serialize_tl_object(create_tl_object<lite_api::liteServer_waitMasterchainSeqno>(wait_mc_seqno, timeout_ms),
+                                 true, std::move(data));
+    }
+    data = create_serialize_tl_object<lite_api::liteServer_query>(std::move(data));
     td::actor::send_closure(server.client, &adnl::AdnlExtClient::send_query, "q", std::move(data),
-                            td::Timestamp::in(8.0), std::move(promise));
+                            td::Timestamp::in(8.0),
+                            [SelfId = actor_id(this), promise = std::move(promise), server_idx,
+                             wait_mc_seqno](td::Result<td::BufferSlice> R) mutable {
+                              if (R.is_ok()) {
+                                td::actor::send_closure(SelfId, &ProxyLiteserver::process_query_response,
+                                                        R.ok().clone(), server_idx, wait_mc_seqno);
+                              }
+                              promise.set_result(std::move(R));
+                            });
+  }
+
+  void process_query_response(td::BufferSlice data, size_t server_idx, BlockSeqno wait_mc_seqno) {
+    auto F = fetch_tl_object<lite_api::Object>(data, true);
+    if (F.is_error() || F.ok()->get_id() == lite_api::liteServer_error::ID) {
+      return;
+    }
+    BlockSeqno new_seqno = wait_mc_seqno;
+    lite_api::downcast_call(*F.ok_ref(), td::overloaded(
+                                             [&](lite_api::liteServer_masterchainInfo& f) {
+                                               new_seqno = std::max<BlockSeqno>(new_seqno, f.last_->seqno_);
+                                             },
+                                             [&](lite_api::liteServer_masterchainInfoExt& f) {
+                                               new_seqno = std::max<BlockSeqno>(new_seqno, f.last_->seqno_);
+                                             },
+                                             [&](lite_api::liteServer_accountState& f) {
+                                               if (f.id_->workchain_ == masterchainId) {
+                                                 new_seqno = std::max<BlockSeqno>(new_seqno, f.id_->seqno_);
+                                               }
+                                             },
+                                             [&](auto& obj) {}));
+    servers_[server_idx].last_known_masterchain_seqno =
+        std::max(servers_[server_idx].last_known_masterchain_seqno, new_seqno);
+    if (new_seqno > last_known_masterchain_seqno_) {
+      last_known_masterchain_seqno_ = new_seqno;
+      LOG(INFO) << "Last known masterchain seqno = " << new_seqno;
+    }
   }
 
   void alarm() override {
@@ -307,11 +378,15 @@ class ProxyLiteserver : public td::actor::Actor {
     liteclient::LiteServerConfig config;
     td::actor::ActorOwn<adnl::AdnlExtClient> client;
     bool alive = false;
+    BlockSeqno last_known_masterchain_seqno = 0;
   };
   std::vector<Server> servers_;
 
   std::map<int, td::uint32> ls_stats_;  // lite_api ID -> count, 0 for unknown
 
+  BlockSeqno last_known_masterchain_seqno_ = 0;
+  tl_object_ptr<lite_api::liteServer_masterchainInfoExt> last_masterchain_info_;
+
   std::string config_file() const {
     return db_root_ + "/config.json";
   }