diff --git a/tool/run/image/uboot b/tool/run/image/uboot
index 5cf5f1ed44..d17e21fa40 100644
--- a/tool/run/image/uboot
+++ b/tool/run/image/uboot
@@ -11,12 +11,31 @@
 proc image_uboot_use_no_gzip { } { return [get_cmd_switch --image-uboot-no-gzip] }
 
 
+##
+# Make gzip compression more aggressive
+#
+# Using this option reduces the image size by circa 10%. But it comes at the
+# cost of significantly slowing down the gzip step for large images (e.g., 6
+# seconds instead of 2 seconds for a image of 13 MiB). The option is suitable
+# when building a release. But for quick build-test cycles, it is best keep
+# it disabled.
+#
+proc image_uboot_gzip_opt { } {
+	if {[get_cmd_switch --image-uboot-gzip-best]} {
+		return "--best"
+	} else {
+		return "--fast"
+	}
+}
+
+
 ##
 # Build U-boot bootloader specific uImage
 #
 # \param  elf_img   ELF binary to build uImage from
 #
 proc run_image {elf_img} {
+
 	# parse ELF entrypoint and load address
 	set entrypoint [exec [cross_dev_prefix]readelf -h $elf_img | \
 			grep "Entry point address: " | \
@@ -34,7 +53,7 @@ proc run_image {elf_img} {
 
 	# compress ELF
 	if $use_gzip {
-		exec gzip --best --force $bin_img
+		exec gzip [image_uboot_gzip_opt] --force $bin_img
 		set bin_ext .gz
 		set compress_type gzip
 	}
diff --git a/tool/run/image/uboot_fit b/tool/run/image/uboot_fit
index 801777a24f..51309cdc6c 100644
--- a/tool/run/image/uboot_fit
+++ b/tool/run/image/uboot_fit
@@ -10,6 +10,19 @@
 #
 proc image_uboot_use_no_gzip { } { return [get_cmd_switch --image-uboot-no-gzip] }
 
+##
+# Make gzip compression more aggressive
+#
+# Please refer to the comment in run/image/uboot.
+#
+proc image_uboot_gzip_opt { } {
+	if {[get_cmd_switch --image-uboot-gzip-best]} {
+		return "--best"
+	} else {
+		return "--fast"
+	}
+}
+
 
 ##
 # Build U-boot bootloader specific image.itb
@@ -34,7 +47,7 @@ proc run_image {elf_img} {
 
 	# compress ELF
 	if $use_gzip {
-		exec gzip --best --force $bin_img
+		exec gzip [image_uboot_gzip_opt] --force $bin_img
 		set bin_ext .gz
 		set compress_type gzip
 	}