diff --git a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/jwt/JwtClaimsSet.java b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/jwt/JwtClaimsSet.java
index d19f2de..360d41d 100644
--- a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/jwt/JwtClaimsSet.java
+++ b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/jwt/JwtClaimsSet.java
@@ -17,7 +17,6 @@ package org.springframework.security.oauth2.jwt;
 
 import org.springframework.util.Assert;
 
-import java.net.URL;
 import java.time.Instant;
 import java.util.Collections;
 import java.util.LinkedHashMap;
@@ -94,7 +93,7 @@ public final class JwtClaimsSet implements JwtClaimAccessor {
 		 * @param issuer the issuer identifier
 		 * @return the {@link Builder}
 		 */
-		public Builder issuer(URL issuer) {
+		public Builder issuer(String issuer) {
 			return claim(ISS, issuer);
 		}
 
diff --git a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2TokenIssuerUtil.java b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2TokenIssuerUtil.java
index fd81e06..f3bf3fb 100644
--- a/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2TokenIssuerUtil.java
+++ b/oauth2-authorization-server/src/main/java/org/springframework/security/oauth2/server/authorization/authentication/OAuth2TokenIssuerUtil.java
@@ -26,9 +26,6 @@ import org.springframework.security.oauth2.jwt.Jwt;
 import org.springframework.security.oauth2.jwt.JwtClaimsSet;
 import org.springframework.security.oauth2.jwt.JwtEncoder;
 
-import java.net.MalformedURLException;
-import java.net.URI;
-import java.net.URL;
 import java.time.Duration;
 import java.time.Instant;
 import java.time.temporal.ChronoUnit;
@@ -47,12 +44,7 @@ class OAuth2TokenIssuerUtil {
 	static Jwt issueJwtAccessToken(JwtEncoder jwtEncoder, String subject, String audience, Set<String> scopes) {
 		JoseHeader joseHeader = JoseHeader.withAlgorithm(SignatureAlgorithm.RS256).build();
 
-		// TODO Allow configuration for issuer claim
-		URL issuer = null;
-		try {
-			issuer = URI.create("https://oauth2.provider.com").toURL();
-		} catch (MalformedURLException e) { }
-
+		String issuer = "https://oauth2.provider.com";		// TODO Allow configuration for issuer claim
 		Instant issuedAt = Instant.now();
 		Instant expiresAt = issuedAt.plus(1, ChronoUnit.HOURS);		// TODO Allow configuration for access token time-to-live
 
diff --git a/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/JwtClaimsSetTests.java b/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/JwtClaimsSetTests.java
index 12340c0..2f23fe6 100644
--- a/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/JwtClaimsSetTests.java
+++ b/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/JwtClaimsSetTests.java
@@ -39,7 +39,7 @@ public class JwtClaimsSetTests {
 		JwtClaimsSet expectedJwtClaimsSet = TestJwtClaimsSets.jwtClaimsSet().build();
 
 		JwtClaimsSet jwtClaimsSet = JwtClaimsSet.withClaims()
-				.issuer(expectedJwtClaimsSet.getIssuer())
+				.issuer(expectedJwtClaimsSet.getIssuer().toExternalForm())
 				.subject(expectedJwtClaimsSet.getSubject())
 				.audience(expectedJwtClaimsSet.getAudience())
 				.issuedAt(expectedJwtClaimsSet.getIssuedAt())
diff --git a/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/TestJwtClaimsSets.java b/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/TestJwtClaimsSets.java
index 42cb13e..16a425c 100644
--- a/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/TestJwtClaimsSets.java
+++ b/oauth2-authorization-server/src/test/java/org/springframework/security/oauth2/jwt/TestJwtClaimsSets.java
@@ -15,9 +15,6 @@
  */
 package org.springframework.security.oauth2.jwt;
 
-import java.net.MalformedURLException;
-import java.net.URI;
-import java.net.URL;
 import java.time.Instant;
 import java.time.temporal.ChronoUnit;
 import java.util.Collections;
@@ -29,11 +26,7 @@ import java.util.UUID;
 public class TestJwtClaimsSets {
 
 	public static JwtClaimsSet.Builder jwtClaimsSet() {
-		URL issuer = null;
-		try {
-			issuer = URI.create("https://provider.com").toURL();
-		} catch (MalformedURLException e) { }
-
+		String issuer = "https://provider.com";
 		Instant issuedAt = Instant.now();
 		Instant expiresAt = issuedAt.plus(1, ChronoUnit.HOURS);