diff --git a/packages/next/src/client/components/navigation.test.ts b/packages/next/src/client/components/navigation.test.ts
new file mode 100644
index 0000000000000..05569915dad7f
--- /dev/null
+++ b/packages/next/src/client/components/navigation.test.ts
@@ -0,0 +1,9 @@
+import { ReadonlyURLSearchParams } from './navigation'
+
+describe('next/navigation', () => {
+  it('should be able to construct URLSearchParams from ReadonlyURLSearchParams', () => {
+    const searchParams = new URLSearchParams('?foo=test&bar=test')
+    const readonlySearchParams = new ReadonlyURLSearchParams(searchParams)
+    expect(() => new URLSearchParams(readonlySearchParams)).not.toThrow()
+  })
+})
diff --git a/packages/next/src/client/components/navigation.ts b/packages/next/src/client/components/navigation.ts
index 349927f905a9c..523870d9908ec 100644
--- a/packages/next/src/client/components/navigation.ts
+++ b/packages/next/src/client/components/navigation.ts
@@ -33,6 +33,7 @@ export class ReadonlyURLSearchParams {
   keys: URLSearchParams['keys']
   values: URLSearchParams['values']
   toString: URLSearchParams['toString']
+  size: any | URLSearchParams['size']
 
   constructor(urlSearchParams: URLSearchParams) {
     this[INTERNAL_URLSEARCHPARAMS_INSTANCE] = urlSearchParams
@@ -45,6 +46,7 @@ export class ReadonlyURLSearchParams {
     this.keys = urlSearchParams.keys.bind(urlSearchParams)
     this.values = urlSearchParams.values.bind(urlSearchParams)
     this.toString = urlSearchParams.toString.bind(urlSearchParams)
+    this.size = urlSearchParams.size
   }
   [Symbol.iterator]() {
     return this[INTERNAL_URLSEARCHPARAMS_INSTANCE][Symbol.iterator]()