SALVADOR, Dec. 3 (Xinhua) -- World football's governing body FIFA is set to resist pressure to change kickoff times for next year's World Cup.

Speaking during a press conference on Tuesday, FIFA secretary general Jerome Valcke rejected fears stifling tropical heat in some Brazilian cities would put players' health at risk.

"This decision was not taken while seated in the snow of Zurich," Valcke said of the tournament fixture.

"It was taken based on medical reports taking into account the country's climate. It could be 12 degrees (Celsius) in Porto Alegre and 28 degrees in Manaus.

"Fixtures were organized so that no match will occur at 1pm in those conditions (28 degrees). We are fully aware of the climatic conditions."

More than a third of the World Cup's 64 matches are scheduled to start at 1pm. Two fixtures are programmed at 3pm and 11 at 4pm.

While the tournament will be held during Brazil's winter months, temperatures in the cities of Salvador, Natal, Recife, Fortaleza, Manaus and Cuiaba often surpass 30 degrees Celsius in June and July.