Complex sentence: The vast expertise available with the ICAS is utilised by the government at the various levels of decision making as well as by International Monitory Fund (IMF) in a number of countries for advising on financial management and accounting functions.
Split into simpler sentences: The vast expertise available in the ICAS has been utilised by the government at the various levels of decision making. The expertise of ICAS officers has also been utilised by International Monitory Fund in a number of countries for advising on various treasury and accounting functions.