Under a faction deal, Senator Lisa Singh has been relegated to an unwinnable fourth spot on the Senate ticket, putting an end to her federal political career at the next election.

It has prompted the New Town branch of the Labor Party to write to Senator Anne Urquhart, convenor of the Left faction, to complain about the move, labeling it ‘‘appalling’’ and a ‘‘potentially destructive move for the party’’.

‘‘The branch simply thinks that dropping Lisa from her place on the Senate ticket is a fundamentally flawed decision,’’ the letter said.

Senator Singh has unsuccessfully lodged a dispute about the eligibility of union votes during the preselection process.

The former state minister was bumped down on the ticket to make way for union official John Short.

The national executive has the power to intervene to reshuffle the order but Mr Shorten said the rank and file had spoken.

‘‘It is inevitable that not everyone is successful in being able to get the spot they want to represent Labor,’’ Mr Shorten said.

‘‘Lisa Singh has served Labor well in the Senate and our new Senate team will also do the same thing.

‘‘It’s always a difficult matter but the rank and file have spoken,’’ he said.

Senator Singh said she had no plans to leave the party or distance herself from it.

‘‘Why you would do a factional deal to knock someone in the front bench down is beyond me,’’ Senator Singh said.

‘‘I’m very much part of the Labor Party, my record speaks for itself.’’

Mr Short said the preselection process was ‘‘very democratic’’.

‘‘I do think I’ve got the support of the Labor Party,’’ Mr Short said.

‘‘I think I’m a reasonable candidate because I’ve got a lot of life experience. 

‘‘I know what it’s like to struggle.’’

Franklin Labor MHA Lara Giddings said Senator Singh had been treated with ‘‘proper party process’’.

‘‘I have the highest respect for her,’’ Ms Giddings said.

‘‘It’s a very difficult issue to say who is better than who – everybody comes to the table with strengths, everybody has a lot to contribute.

‘‘I’d be very sorry too to see a talent like Lisa Singh lost.’’