diff --git a/src/core/thread/mle.cpp b/src/core/thread/mle.cpp
index 91501c6e4..4bfe4aa5e 100644
--- a/src/core/thread/mle.cpp
+++ b/src/core/thread/mle.cpp
@@ -624,7 +624,7 @@ otError Mle::BecomeChild(AttachMode aMode)
     otError error = OT_ERROR_NONE;
 
     VerifyOrExit(mRole != OT_DEVICE_ROLE_DISABLED, error = OT_ERROR_INVALID_STATE);
-    VerifyOrExit(mAttachState == kAttachStateIdle, error = OT_ERROR_BUSY);
+    VerifyOrExit(!IsAttaching(), error = OT_ERROR_BUSY);
 
     if (mReattachState == kReattachStart)
     {
diff --git a/src/core/thread/mle.hpp b/src/core/thread/mle.hpp
index bd345824c..eaf101a9c 100644
--- a/src/core/thread/mle.hpp
+++ b/src/core/thread/mle.hpp
@@ -602,6 +602,19 @@ public:
      */
     bool IsAttached(void) const;
 
+    /**
+     * This method indicates whether device is currently attaching or not.
+     *
+     * Note that an already attached device may also be in attaching state. Examples of this include a leader/router
+     * trying to attach to a better partition, or a child trying to find a better parent (when feature
+     * `OPENTHREAD_CONFIG_PARENT_SEARCH_ENABLE` is enabled).
+     *
+     * @retval TRUE   Device is currently trying to attach.
+     * @retval FALSE  Device is not in middle of attach process.
+     *
+     */
+    bool IsAttaching(void) const { return (mAttachState != kAttachStateIdle); }
+
     /**
      * This method returns the current Thread interface state.
      *
diff --git a/src/core/thread/mle_router.cpp b/src/core/thread/mle_router.cpp
index 125fcf680..99ce3178c 100644
--- a/src/core/thread/mle_router.cpp
+++ b/src/core/thread/mle_router.cpp
@@ -416,7 +416,7 @@ otError MleRouter::SendAdvertisement(void)
     // Without this suppression, a device may send an MLE Advertisement before receiving the MLE Child ID Response.
     // The candidate parent then removes the attaching device because the Source Address TLV includes an RLOC16 that
     // indicates a Router role (i.e. a Child ID equal to zero).
-    VerifyOrExit(mAttachState == kAttachStateIdle);
+    VerifyOrExit(!IsAttaching());
 
     // Suppress MLE Advertisements when transitioning to the router role.
     //
@@ -573,7 +573,7 @@ otError MleRouter::HandleLinkRequest(const Message &aMessage, const Ip6::Message
 
     VerifyOrExit(mRole == OT_DEVICE_ROLE_ROUTER || mRole == OT_DEVICE_ROLE_LEADER, error = OT_ERROR_INVALID_STATE);
 
-    VerifyOrExit(mAttachState == kAttachStateIdle, error = OT_ERROR_INVALID_STATE);
+    VerifyOrExit(!IsAttaching(), error = OT_ERROR_INVALID_STATE);
 
     // Challenge
     SuccessOrExit(error = Tlv::GetTlv(aMessage, Tlv::kChallenge, sizeof(challenge), challenge));
@@ -1603,7 +1603,7 @@ otError MleRouter::HandleParentRequest(const Message &aMessage, const Ip6::Messa
     // A Router MUST NOT send an MLE Parent Response if:
 
     // 0. It is detached or attempting to another partition
-    VerifyOrExit((mRole != OT_DEVICE_ROLE_DETACHED) && (mAttachState == kAttachStateIdle), error = OT_ERROR_DROP);
+    VerifyOrExit((mRole != OT_DEVICE_ROLE_DETACHED) && !IsAttaching(), error = OT_ERROR_DROP);
 
     // 1. It has no available Child capacity (if Max Child Count minus
     // Child Count would be equal to zero)
@@ -3287,7 +3287,7 @@ Neighbor *MleRouter::GetNeighbor(const Mac::ExtAddress &aAddress)
             ExitNow();
         }
 
-        if (mAttachState != kAttachStateIdle)
+        if (IsAttaching())
         {
             rval = Mle::GetNeighbor(aAddress);
         }