LONDON (AFP/REUTERS) - The Pentagon-run programme to train and equip moderate Syrian rebels to fight Islamic State in Iraq and Syria (ISIS) militants is being overhauled, United States officials said on Friday (Oct 9).

Speaking at a news conference in London, US Defence Secretary Ashton Carter said he had been dissatisfied with the effort, which suffered disastrous blows in its early days.

"We have devised a number of different approaches... going forward," Mr Carter said.

A senior US defence official, speaking on condition of anonymity, later said the programme was being "refocused to enhance its effectiveness".

The official said some training and embedding of rebels would continue to take place, but did not elaborate.

He said the programme not "ending" but is instead being refocused, the senior defence official said, who spoke on condition of anonymity to reporters traveling with Mr Carter ahead of an announcement on overhauling the troubled US effort.

The initial results of the programme were roundly denounced as a flop, with one group of trainees giving ammunition and other equipment to an Al-Qaeda-affiliated group in Syria.

Mr Carter said the new US effort would seek to enable Syrian rebels in much the way the United States had helped Syrian Kurdish forces to successfully battle ISIS.

"The work we've done with the Kurds in northern Syria is an example of an effective approach where you have a group that is capable, motivated on the ground, that you can enable their success," Mr Carter said. "That's exactly the kind of example that we would like to pursue with other groups in other parts of Syria going forward. That is going to be the core of the President's concept."

The decision would be announced later on Friday, he told journalists, saying: "I think you'll be hearing very shortly from him in that regard about the proposals that he has approved and that we are going to go forward with."

In May, the US military began training for up to 5,400 fighters a year in what was seen as a test of President Barack Obama's strategy of having local partners combat ISIS militants and keep US troops off the front lines.

But the programme was troubled from the start, with some of the first class of less than 60 fighters coming under attack from Al-Qaeda's Syria wing, Nusra Front, in their battlefield debut.

Reuters reported last week that the Obama administration was considering extending support to thousands of Syrian rebel fighters, possibly with arms and air strikes, as part of the revamped approach to Syria.

That includes rebels near the border with Turkey and members of the Syrian Arab Coalition.