* Move will trigger early election
* Election expected to be held in the autumn
PRAGUE, Aug 8 (Reuters) - The lower house of the Czech parliament will hold a session to dissolve itself some time next week, opening the way to an early election, two deputies told Reuters.
The decision comes a day after the chamber voted against giving a vote of confidence to the government of Prime Minister Jiri Rusnok.
The Czech government was thrown into disarray in June after the centre-right cabinet of Prime Minister Petr Necas collapsed over a graft and spying scandal.
President Milos Zeman then appointed his supporter Rusnok to form a cabinet, bypassing political parties that had proposed other options and accused Zeman of grabbing powers that belong to parliament.
"We have not agreed on a date yet. The extraordinary session should take place next week," Pavel Kovacik, the chairman of the Communist party caucus told Reuters.
Separately, Deputy Speaker Jan Hamacek, member of the centre-left Social Democrats, confirmed the vote would take place some time next week.
An election could then be held in the autumn, most likely in October.
The vote on Wednesday showed Rusnok did not have enough support from leftist parties to rule. But it also showed centre-right factions in parliament, which had claimed having 101 votes in the 200-seat house, had lost several deputies and was not a viable alternative to form a government.
The break prompted the conservative TOP09 party, part of the centre-right grouping, to join earlier calls by the main leftist parties and Zeman to hold an early election. Support from TOP09 will likely be enough for the early election motion to be approved.
Czech Social Democrat party leader Bohuslav Sobotka said on Thursday he believed there was sufficient support for a motion to dissolve parliament and hold an early election.