UPDATE 1-Taliban pushed back, long way to go-Obama

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LONDON, July 11 (Reuters) - U.S. and allied troops have pushed back Taliban insurgents in a major offensive in Afghanistan but there is still a long way to go, U.S. President Barack Obama said on Saturday.

"We knew that this summer was going to be tough fighting ... They (the Taliban) have, I think, been pushed back but we still have a long way to go. We've got to get through elections," he said in an interview with Sky News during his visit to Ghana.

He said the United States and its allies would have to evaluate the situation after Afghanistan's Aug. 20 presidential election to see what more they could do. "It may not be on the military side, it may be on the development side," he said.

U.S. and British forces are both involved in fierce fighting in the Taliban bastion of Helmand in southern Afghanistan.

Obama praised the "extraordinary role" British soldiers had played in Afghanistan and said his heart went out to the families of eight British soldiers killed there in the last few days.

Asked whether Washington still needed British forces in Afghanistan now that it was ramping up its forces there, Obama said: "The contribution of the British is critical."

"This is not an American mission. The mission in Afghanistan is one that the Europeans have as much if not more of a stake in than we do ... The likelihood of a terrorist attack in London is at least as high, if not higher, than it is in the United States," he said.

Past and present British prime ministers Tony Blair and Gordon Brown had not committed troops to Afghanistan because they wanted to "put their young men and women in harm's way," he said.

"It's because of a recognition that we've got a serious fight on our hands and we've got to deal with it smartly, but we've got to deal with it effectively," he said.

The most important thing was for Washington and its allies to combine their military efforts in Afghanistan with effective diplomacy and development "so that Afghans feel a greater stake and have a greater capacity to secure their country," he said.

After next month's election, "we need to start directing our attention to how do we create an Afghan army, an Afghan police, how do we work with the Pakistanis effectively so that they are the ones who are at the forefront of controlling their own countries?" Obama said. (Reporting by Adrian Croft; Editing by Jon Boyle)