By Natalie Grover and Noah Browning LONDON (Reuters) -Oil prices fell by more than 4% on Monday on sharp price cuts by top exporter Saudi Arabia and a rise in OPEC output, offsetting supply concerns generated by escalating geopolitical tension in the Middle East. Brent crude slid 4.2%, or $3.38, to $75.38 a barrel by 1440 GMT while U.S. West Texas Intermediate crude futures lost 4.7%, or $3.52, to $70.29. Both contracts climbed more than 2% in the first week of 2024 on intensifying geopolitical risk in the Middle East after attacks by Yemen’s Houthis on ships in the Red Sea. On Sunday rising s…