The Australian man who was jailed for disrupting London's annual university boat race has been told to leave Britain despite the fact his wife is pregnant.

Trenton Oldfield, 37, was jailed for six months after he jumped into the River Thames in April 2012 and swam between the universities' boats.

It was the first time in the 158-year history of the annual Oxbridge race that it had been interrupted by a swimmer.

After his release from prison, Mr Oldfield again courted controversy by saying the use of 200 Marines to prevent any protests at this year's event amounted to the "militarisation of public space".

He has now been ordered to leave the country.

"Those who come to the UK must abide by our laws," a spokesman for Britain's Home Office said.

"We refused this individual leave to remain because we do not believe his presence in this country is conducive to the public good."

Mr Oldfield, whose British wife Deepa Naik is expecting a child, says he has appealed against the decision.

We have every hope this deportation escalation was just a bureaucratic mistake and the Home Office sends a note to clarify the mistake. — ThisIsNotAGateway(@NotAGateway) June 24, 2013

He also told the Guardian newspaper that the decision was unexpected.

"I have a tier one visa, as a highly skilled migrant, and I was sentenced to less than a year," he said.

"The lawyer said I had nothing to worry about because it was less than a year.

"It feels to me that this is a very vindictive decision, very political and very much an overreaction."

His wife says deportation should be for "violent criminals, major fraudsters and terrorists".

"We can't not live and work together. That's impossible. I can't be separated from him," she told the newspaper.

AFP