Updated

Egypt's Muslim Brotherhood has postponed an open confrontation with the country's military rulers and other political players Tuesday when it delayed a decision about whether to field a candidate for the first presidential elections since the ouster of Hosni Mubarak.

An eight-hour meeting of the Brotherhood's highest leadership body failed to come up with a final decision on whether to reverse an earlier pledge not to contest the presidency.

Further meetings of the Brotherhood's Shura Council were to continue next week and a senior member of the group described the discussions as "comprehensive" and "exhausting."

The lack of a decision Tuesday highlights growing divisions within the group over the thorny presidency question but also the group's hesitancy over a confrontation with the ruling military council and other national forces over the issue.

The Islamist group's increasing grip on power has fueled concerns among liberals and secularists over its intentions and whether it aims to govern alone, controlling both the parliament and the presidency. If it were to run a candidate, it would hike their fears that it aims for a monopoly.

Moreover, it could anger the military. The generals are believed to be aiming to back a consensus candidate for president -- one that would have Brotherhood backing but would also protect the military's interests. If the Brotherhood goes with its own candidate, it would challenge that scenario.

"We discussed all the recent developments. There are many views, but the debate is not settled yet. So they remain points of view," said Mahmoud Hussein, the Brotherhood's secretary general. "We prefer to postpone the discussions so that minds and bodies come prepared and not tired the next round."

More than 100 members of the Brotherhood's Shura Council, which serves as a sort of legislative body for the group, met Tuesday to decide on fielding a presidential candidate, according to a statement on the group's website.

The Brotherhood has emerged as the most powerful political group since Hosni Mubarak was ousted last year, capturing nearly 50 percent of the seats in Egypt's first post-uprising parliament. The group has also claimed a firm majority for Islamists in the 100-member panel that will write the country's post-Mubarak constitution.

If the group makes a presidential bid, it would certainly deepen these fears that the group wants to govern alone. Since Mubarak's ouster, the group has promised not to field a candidate in order to allay those worries.

Given the Brotherhood's popular support and skills at rallying voters, its candidate would stand a strong chance of winning the presidency in late May's elections.

Some members have voiced reservations about the group reversing its earlier promise. A top Brotherhood lawmaker, Mohammed el-Beltagy, told Egypt's Al-Tahrir television late Monday that an internal poll showed a majority of Brotherhood members oppose reversing the pledge not to field a candidate.

Despite its popular appeal, the Brotherhood has been in a tight spot and many of its supporters have grown frustrated with the group's inability to translate its newly gained political clout into real power. The group has in recent weeks been pushing the ruling generals to sack the current military-appointed prime minister and allow the creation of a Brotherhood-led Cabinet. The military council has refused, and the two powerful players appeared on a collision course.

"The honeymoon between the Muslim Brotherhood and the military council ... has reached its logical end," Hassan Nafaa wrote in the Al-Masry Al-Youm daily. "Egypt is stuck between two powers. Each is trying to flex its muscles in the face of the other and impose its will over the other."

Tuesday's inconclusive meeting appeared to have delayed a showdown. Hussein also said there are no plans for the group to take to the streets this weekend in protests against the incumbent government, as local media had reported they would.

The move to consider running a candidate appeared to be rooted in the group's frustrations. According to Al-Masry Al-Youm, two of the top names under consideration as possible nominees are Brotherhood strongman and financier Khairat el-Shater and parliamentary speaker Saad el-Katatni. El-Shater, however, faces a legal barrier to running because of a 2008 conviction on money laundering and terrorism charges.

Some observers believe the Brotherhood-military showdown is little more than a smoke screen to conceal a deal to split power. The Egyptian media has speculated for months of a secret deal between them over a so-called "consensus candidate," whom both the Islamists and the military could support.

Another factor in the Brotherhood's possible bid for the presidency is the challenge from an ex-member, Abdel-Moneim Abolfotoh, who was thrown out of the group because he decided to run despite the group's ban. He has drawn support from many of the Brotherhood's young members because of his moderate stances.

The liberals, leftists and youth groups that led the anti-Mubarak uprising are struggling to get their voices heard in the tug-of-war between the military and the Brotherhood.

Their fears deepened this week, after the Brotherhood and ultraconservative Salafis gave themselves a firm majority of seats on a 100-member constitutional panel. That gives the Islamists the strongest hand in writing the new charter, which will determine the balance of power between Egypt's previously all-powerful president and parliament, and define the country's future identity, including the role of religion and minority rights.

More than a dozen mostly liberal and secular-minded members have withdrawn from the panel, saying the committee does not reflect the diversity of Egyptian society. They plan to write an alternative constitution, and many plan to return to street protests. But some liberals are also calling on the generals to intervene.

"It is up to the Supreme Council of the Armed Forced to get involved," said Sameh Ashour, the head of the lawyer's syndicate who resigned from the panel. "We cannot leave representation of Egypt to a majority in parliament."

The head of Egypt's ruling military council, Field Marshal Hussein Tantawi met with representatives of political parties, including the Brotherhood's political arm, to discuss the standoff a day before the panel was scheduled to meet.

Tantawi said "the constitution must be in the hands of all Egyptians, because it will for a long time chart the road Egypt takes internally and externally." His comments were carried by the official news agency.