A method of driving a mobile communication terminal in a cellular network, includes monitoring with a control unit of the mobile communications terminal, reception power levels between the mobile communication terminal and cellular network base stations at a predefined monitoring rate for each base station. Timing information values for a number of base stations are intermittently monitored by the control unit. Drift of the timing information values for at least two of the base stations is monitored and significant motion of the mobile communication terminal is deemed detected if at least one of the timing information values indicates a drift equal to or exceeding a given timing drift threshold. The predefined reception power level monitoring rate is reduced to a reduced reception power level monitoring rate for at least a number of the base stations as long as the motion of the mobile communication terminal is not significant.