diff --git a/src/core/execution/TransportShipExecution.ts b/src/core/execution/TransportShipExecution.ts
index 3504e691c..e24a9ac3b 100644
--- a/src/core/execution/TransportShipExecution.ts
+++ b/src/core/execution/TransportShipExecution.ts
@@ -4,6 +4,7 @@ import {
   Game,
   MessageType,
   Player,
+  PlayerType,
   TerraNullius,
   Unit,
   UnitType,
@@ -76,6 +77,16 @@ export class TransportShipExecution implements Execution {
       return;
     }
 
+    if (this.target.isPlayer()) {
+      const targetPlayer = this.target as Player;
+      if (
+        targetPlayer.type() !== PlayerType.Bot &&
+        this.attacker.type() !== PlayerType.Bot
+      ) {
+        this.rejectIncomingAllianceRequests(targetPlayer);
+      }
+    }
+
     if (this.target.isPlayer() && !this.attacker.canAttackPlayer(this.target)) {
       this.active = false;
       return;
@@ -290,4 +301,13 @@ export class TransportShipExecution implements Execution {
   isActive(): boolean {
     return this.active;
   }
+
+  private rejectIncomingAllianceRequests(target: Player) {
+    const request = this.attacker
+      .incomingAllianceRequests()
+      .find((ar) => ar.requestor() === target);
+    if (request !== undefined) {
+      request.reject();
+    }
+  }
 }
diff --git a/tests/Attack.test.ts b/tests/Attack.test.ts
index dbf05b7c2..5f741559f 100644
--- a/tests/Attack.test.ts
+++ b/tests/Attack.test.ts
@@ -333,6 +333,54 @@ describe("Attack race condition with alliance requests", () => {
   });
 });
 
+describe("Transport ship alliance rejection", () => {
+  beforeEach(async () => {
+    game = await setup("ocean_and_land", {
+      infiniteGold: true,
+      instantBuild: true,
+      infiniteTroops: true,
+    });
+
+    const playerAInfo = new PlayerInfo(
+      "playerA",
+      PlayerType.Human,
+      null,
+      "playerA_id",
+    );
+    // close to the water to send boats
+    playerA = addPlayerToGame(playerAInfo, game, game.ref(7, 0));
+
+    const playerBInfo = new PlayerInfo(
+      "playerB",
+      PlayerType.Human,
+      null,
+      "playerB_id",
+    );
+    playerB = addPlayerToGame(playerBInfo, game, game.ref(7, 15));
+
+    while (game.inSpawnPhase()) {
+      game.executeNextTick();
+    }
+  });
+
+  test("Should cancel alliance requests if the recipient sends a transport ship", async () => {
+    // Player A sends alliance request to Player B
+    const allianceRequest = playerA.createAllianceRequest(playerB);
+    expect(allianceRequest).not.toBeNull();
+    expect(playerB.incomingAllianceRequests()).toHaveLength(1);
+
+    // Player B sends a transport ship toward Player A's territory
+    game.addExecution(new TransportShipExecution(playerB, game.ref(7, 0), 0));
+
+    // Execute a tick to process the transport ship launch
+    game.executeNextTick();
+
+    // Alliance request should be rejected since player B sent a naval invasion
+    expect(playerA.outgoingAllianceRequests()).toHaveLength(0);
+    expect(playerB.incomingAllianceRequests()).toHaveLength(0);
+  });
+});
+
 describe("Attack immunity", () => {
   beforeEach(async () => {
     game = await setup("ocean_and_land", {