Kevin Rudd has preempted gathering speculation about a leadership showdown next week by resigning as foreign minister in a dramatic late night press conference in Washington DC.

Rudd blamed the lack of support from senior colleagues and the Prime Minister, citing Julia Gillard’s failure today to repudiate attacks on him by Simon Crean and others this week.

“I cannot continue to serve as foreign minister if I don’t have Prime Minister Gillard’s support. Therefore the only honourable thing and honourable course of action is to resign. I do so with a genuinely heavy heart and after much personal reflection” he said. He also said he would have preferred to resign in Australia rather than overseas.

It was unclear whether Rudd had informed the Prime Minister of his decision beforehand.

Rudd also said that the “ongoing saga” of the leadership had become, in the view of Australians, “little better than a soap opera” of which he no longer wanted to take part. It was also, he said, damaging the electoral prospects of Anna Bligh in the Queensland election.

Rudd also took a swipe at the party’s “faceless men”, saying that the party must be fundamentally reformed to end their power: “in Australia, the people must rule, not the factions.” He would not, he said, be party to a “stealth attack on a sitting prime minister”, a clear reference to his own fate as Prime Minister. Since losing the Prime Ministership, Rudd has often painted himself as an enemy of the vested interests of the party, in a manner similar to that of Peter Beattie, who successfully won an election in Queensland in the aftermath of the Shepherdson Inquiry by painting himself as the reformer of his own party.

However, Rudd has left his options open, indicating he would be consulting with “his family, the community and parliamentary colleagues” once he arrives back in Brisbane on Friday and that he would be making a statement about his future before parliament resumes on Monday.

That leaves open the option of challenging for the prime ministership, or resigning from parliament — the latter option being one that will fill the Gillard camp with deep worry. Rudd’s seat of Griffith was a marginal seat before he secured it in 1998 and is easily winnable for the Coalition on current polling.

A third option, of simply remaining on the backbench, appears unlikely.

Rudd’s decision comes after increasing signals from the Gillard camp today that they believed they had his measure, with suggestions the foreign minister should be sacked and the Prime Minister force him to show his hand by spilling the leadership. Rudd has now seized back the initiative and can keep the Gillard camp — and his colleagues —  guessing about what he has in store for the government next week.

However, he may have tipped his hand as to his intentions with his comment “there is one overriding question for my caucus colleagues and that is who is best placed to defeat Tony Abbott? Mr Abbott doesn’t have the temperament or the experience to hold the high office of the prime minister of Australia but at present, and for a long time now, he’s been on track to do just that.”

That may well be the exact line Rudd will adopt in his “consultations” with colleagues about his “next steps”, in his pitch to convince the party that Julia Gillard will inevitably lead the party to defeat.

Regardless, the most accurate observation made by Rudd is that the “ongoing saga” of the Labor leadership has become in the eyes of voters a “soap opera”. It is one that will now continue at an even more melodramatic level into next week when, one feels, Rudd will throw down the gauntlet to the woman who ousted him from the prime ministership — and the “faceless men” who back her.

At 8.09pm Julia Gillard issued the following statement

RESIGNATION OF KEVIN RUDD

Today Kevin Rudd has tendered his resignation as Minister for Foreign Affairs.

Mr Rudd was a strong and effective advocate for Australia’s interests overseas.

During his period of service as Foreign Minister there were many achievements. He strongly pursued Australia’s interests in the world.

I am disappointed that the concerns Mr Rudd has publicly expressed this evening were never personally raised with me, nor did he contact me to discuss his resignation prior to his decision.

I plan to hold a press conference tomorrow to make a further statement.

Note that Gillard refers to Rudd’s failure to consult “prior to his decision” but not his announcement.