* Opposition says will fight for 13 disputed districts
* Numbers of protesters at election offices dwindle
* Yanukovich leadership blocks bid for partial recount
By Richard Balmforth
KIEV, Nov 6 (Reuters) - Ukraine's opposition sought on Tuesday to keep up pressure over an election they say was rigged, but the leadership of President Viktor Yanukovich blocked their bid for a partial recount.
Deputies from Yanukovich's Party of the Regions traded charges in parliament with the bloc of jailed ex-Prime Minister Yulia Tymoshenko about an election where the ruling party seems to have held its majority despite a strong opposition showing.
International monitors say the Oct. 28 election in the former Soviet republic of 46 million was flawed in its run-up and marred by attempts to massage results in the vote count.
Tymoshenko's Batkivshchyna (Fatherland), far-right nationalists and a liberal party headed by boxing champion Vitaly Klitschko, have held street protests over the election despite winning seats in the 450-member parliament.
But the Yanukovich government signalled it would fight opposition attempts to win a recount in 13 electoral districts where they say their candidates were cheated out of victory.
"Once again we're hearing calls for destabilisation," said Prime Minister Mykola Azarov, referring to the 2004-5 "Orange Revolution" street protests against vote-rigging which doomed Yanukovich's first bid for the presidency.
"We have no extra money for absurd ideas. The country has held elections. It has formed a parliament. It will work according to its schedule," he said.
The outgoing parliament, dominated by Yanukovich's party and its allies, stalled opposition pressure for a partial recount by setting up a committee to look into the issue.
Central electoral authorities on Monday offered to meet the opposition half-way, proposing to hold a re-run of the vote in a handful of districts. But Batkivshchyna rejected that and deputies questioned whether election authorities had the right to make such an offer.
Even if the 13 contested seats were to go to the opposition, they would not upset the final outcome of the election in which the Party of the Regions can secure a majority of more than 225 seats, assuming help from traditional parliamentary allies such as the communists.
Yanukovich's pro-business Regions, which is financed by wealthy industrialists, say they alone can provide stability in the country which is a major exporter of steel and grain.
The opposition accuses the government of fostering corruption and cronyism and wants to stop him securing a second term as president in 2015.
Opposition leaders said they would press on with their demands. But with the numbers of demonstrators at election headquarters in Kiev down to just a few hundred, the steam seemed to be running out of the protest.
Under election law, Ukrainian authorities have until Nov. 12 to announce preliminary overall results and binding official results by Nov. 17.
"We are demanding that the central electoral committee conduct a count of the vote (in the 13 districts) and announce our candidates the winners," Arseny Yatseniuk, a former economy minister who heads the united opposition in the absence of Tymoshenko, told journalists.
"We will not vote for a farce. We will demand from President Yanukovich that he be the guarantor of the constitution and not the guarantor of fraud," he said.
Klitschko, the WBC world heavweight champion who heads the UDAR (Punch) party, said: "Up to Nov. 12 we will continue to keep up moral pressure on those at the central electoral commission and the presidential administration and will show them that votes should not simply be stolen."