KIEV, May 16 (Reuters) - Ukraine's feuding president and prime minister failed again on Wednesday to agree on a date for an election, prolonging political uncertainty.

In April pro-Western President Viktor Yushchenko dissolved the largely hostile parliament and ordered the poll in an attempt to end months of disagreements with Prime Minister Viktor Yanukovych, who favors Moscow.

Yanukovich opposed the vote for weeks but eventually agreed. The two leaders held talks last weekend and their camps said after that meeting they were "100 percent" confident the long-awaited date for the election would be set on Wednesday.

But after more than a week of talks, a working group which brings together all parties involved in the conflict failed on Tuesday to agree on a draft of laws needed for the new poll.

"Yushchenko and ... Yanukovych proposed the working group must work to accomplish whatever can be agreed upon in one or two days," Security Council head Ivan Pliushch told journalists after Yushchenko met Yanukovich on Wednesday.

"The (election) date will be named after final agreements." He declined to say when that point could be reached.

Yushchenko favors a date at the end of June or beginning of July, Yanukovich's allies say the polls cannot be held earlier than September, and preferably in October.

First Deputy Prime Minister Mykola Azarov, a Yanukovych loyalist in the premier's Regions Party, said there was no agreement because "of the hugeness and complexity of the problems." He also declined to elaborate.

Yushchenko had threatened the working group there could be no further delays and he could force a decision through the Security Council if no deal was reached.

Yushchenko surprised many on Saturday by dismissing the head of the Security Council, wealthy industrialist Vitaly Haiduk, and appointing Pliushch, a skilful Soviet-era functionary and a former parliament speaker, to the post.

Yushchenko beat Yanukovych in a rerun of a rigged 2004 presidential election and has promoted NATO and European Union membership and liberal economic policies. (rt/ez)