ISRAELI forces carried out strikes across Gaza today as they pressed ahead with an invasion that officials say could go on for months, even as global calls for a ceasefire left both Israel and its main ally, the United States, increasingly isolated.

The offensive has already brought unprecedented death and destruction to the impoverished coastal enclave: much of northern Gaza has been obliterated, more than 18,000 Palestinians killed, and over 80 per cent of the population of 2.3 million pushed from their homes.

The health system and aid operations have collapsed in large parts of the besieged territory, and aid workers have warned of starvation and the spread of disease among displaced people in overcrowded shelters and tent camps.