In his final speech as prime minister in June, Mr Rudd hoped Labor wouldn't lurch to the right on the issue of asylum seekers.
Liberal senator Mitch Fifield said this showed Mr Rudd would clash with Ms Gillard in his new ministerial role.
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"Kevin Rudd, we know, is opposed to the offshore processing proposal at East Timor that the prime minister has put forward," he told Sky News.
But incoming Labor frontbencher Mark Butler dismissed Senator Fifield's assertion as inference and said Mr Rudd would recognise government policy.
"I'm sure that he will take to this task along with Chris Bowen as the new minister for immigration and make great headway with the East Timorese," he said.
Senator Fifield said Mr Rudd as prime minister said unflattering things about the Chinese during the 2009 Copenhagen climate change conference and harmed Australia's relations with Japan over the whaling issue.
