pallou Palau has a blue flag with a yellow circle.
Brazil has a green flag with a blue circle inside a yellow diamond.
The country with a green flag and yellow diamond is Brazil. The flag features a green field with a yellow diamond in the center containing a blue circle with 27 white stars arranged in the pattern of the night sky over Rio de Janeiro on November 15, 1889.
The flag you may be referring to is that of Argentina, which features a light blue and white alternating stripe pattern with a golden sun with the face at its center.
The Swedish flag is blue, with a yellow cross on it.
Romania
Red, Green, Blue, Yellow and Black rings on a white field.
Several countries have a blue, yellow, red, and white flag:KiribatiCape VerdeMalaysiaPhilippinesSerbiaSloveniaTuvaluIn addition, the Buddhist flag is blue, yellow, red, and white.
Barbados
The colors are red, yellow, orange and blue. The bottom half of the flag is blue, with an orange star in the middle, and alternating rays of red and yellow in the top half.
The colors are red, yellow, orange and blue. The bottom half of the flag is blue, with an orange star in the middle, and alternating rays of red and yellow in the top half.
Blue, and a number of yellow stars making a circle in the middle.