Armando Siahaan & Markus Junianto Sihaloho – Megawati Sukarnoputri's defiant statement that the Indonesian Democratic Party of Struggle will remain in the opposition rather than joining the ruling coalition will adversely affect President Susilo Bambang Yudhoyono's Democratic Party, analysts said on Thursday.

Karel Harto Susetyo, a political analyst for consulting firm Charta Politika, said now that Megawati's party, also known as PDI-P, was off the table, it would weaken the Democrats' bargaining position among the opposition bloc and the dissenting parties in the coalition itself.

During the House of Representatives vote on the Bank Century inquiry last month, the ruling coalition was essentially fractured when Golkar, the Prosperous Justice Party (PKS) and the United Development Party (PPP), all key members of the coalition, turned against the Democrats and found that the rescue was illegal.

The dissent sparked speculation that the Democrats would reconfigure the coalition by ousting the rebellious parties and forming a partnership with the PDI-P.

The likelihood of such a scenario was strengthened by reports that key PDI-P figures such as Taufik Kiemas, chairman of the party's advisory board and husband of Megawati, were considering the unlikely merger.

But the possible partnership was effectively quashed at the PDI-P's national congress on Tuesday, when Megawati said the party would remain in opposition to the Democrat-led government.

Karel said that this could hamper Yudhoyono's agenda, including efforts to pass bills in the House, Karel added that the most immediate impact would be felt in relation to the ongoing tax debacle. The arrest of rogue tax official, Gayus Tambunan has led some factions in the House, including Golkar and the PKS, to propose the launch of another special committee, this time to investigate the tax system.

"This whole tax thing will be a prolonged case," he said. "This is something in which the Democrats will have no control over the outcome."

Karel said Golkar and the PKS might try to capitalize on this by pursuing a goal that they failed to achieve during the Bank Century saga – ousting Finance Minister Sri Mulyani and Vice President Boediono.

"In the end, they will target Sri Mulyani," he said. "Once it enters the House, everything will be politicized and it will be hard for the Democrats" to assert their influence.

Political researcher Sunny Tanuwidjaja, of the Center for Strategic and International Studies, said that the PDI-P's unwillingness to join the coalition would be a concern for the Democrats. However, Sunny said that it would still be possible to gain PDI-P support by making concessions such as appointing officials endorsed by the party.

But on Thursday, following the inauguration ceremony of Megawati as the party's chairwoman, Taufik released a statement that indicated his dissatisfaction over the party's pledge to remain in the opposition, but apparently he still held out hope "The [coalition] door is not actually closed," he said.