In the wake of terror attacks in Mumbai, the US, Britain and Australia have advised its citizens to defer travel to India's commercial capital till further notice.

The three nations issued travel advisories warning its nationals that terrorists in India were "deliberately" targeting westerners.

"Due to fluid situation in Mumbai, Americans are urged to defer travel to Mumbai for at least the next 48-72 hours," according to the travel advisory issued by the US Embassy here.

It noted that terrorists attacked two hotels, a railway station, restaurant, hospital and other locations in Mumbai frequented by westerners.

"Some of the casualties are foreigners, and media reports indicate Americans have been targeted," it noted.

British High Commission here has advised Britons against all but essential travel to Mumbai until further notice.

"We advise all British nationals in the city (Mumbai) to stay indoors until local authorities advise that it is safe to go outside," it said.

The Australian High Commission asked its nationals to exercise "extreme caution" if they decided to travel to India.

"The Mumbai attacks show terrorists in India are deliberately targeting westerners. Further attacks cannot be ruled out," according to the advisory issued by the Australian High Commission.

"Australians should avoid travel to Mumbai at this time," it said.