Why xterm fails to set foreground or background color in Red Hat Enterprise Linux 7 ?

Issue

• The command xterm -fg or xterm -bg do not work on RHEL7 unless both -bg and -fg options are defined.
• Running the command xterm -fg xx will change the color of the scroll bar but does not change the foreground text color.

# /usr/bin/xterm -fg red
Warning: Color name "WINDOW_BACKGROUND" is not defined
xterm: unable to allocate fg/bg colors
#

• Running the command xterm -bg xx will change the color of the scroll bar but does not change the background color.

# xterm -bg green
xterm: unable to allocate fg/bg colors
Warning: Color name "WINDOW_FOREGROUND" is not defined
#

• Specifying both, foreground and background colors works correctly.

# xterm -bg green -fg red