* Rift over alleged corruption rocks centre-right coalition
* Public Affairs stays in coalition, leader quits cabinet
* PM says more cabinet changes to come later this spring
(Adds PM, quotes, background)
PRAGUE, April 8 (Reuters) - The leader of a junior Czech coalition party quit the cabinet on Friday amid allegations of corruption, easing tension in the centre-right coalition.
Vit Barta, informal leader of the centrist Public Affairs party, resigned as transport minister but his party remained in the coalition, which has promised to cut the budget deficit and reform pensions and health care.
Public Affairs, which won 10.9 percent of the vote in last year's election, has been a destabilising factor in a coalition led by the Civic Democrats of Prime Minister Petr Necas.
The government won investor confidence by pledging to balance the budget by 2016 and push through widespread reforms, but its efforts have been hampered by a series of graft scandals and clashes within and between the three coalition parties.
"We will continue to support the coalition cabinet, on the condition that (the anti-corruption) cleansing process at the transport ministry continues," Public Affairs party Chairman Radek John said in a live interview with Czech Television.
Prime Minister Petr Necas said he accepted the resignation, which he called a necessary step given the weight of the allegations. He said there would be further changes to some cabinet posts later this spring.
Signalling possible further coalition squabbles, Necas said he would raise questions about the Public Affairs party's control of the interior ministry, given that Barta used to run a private detective agency which had tailed politicians.
Barta, the party's most influential figure and its main financial backer, has denied any wrongdoing after two of the party's parliamentary deputies accused him of handing out cash payments to them for being loyal to the party's leadership.
The party expelled three dissenting members of its 24-strong parliamentary caucus this week, reducing the coalition's majority in the 200-seat lower house to 115.
Political analysts have said the Public Affairs party may split up, but the coalition would still find enough support in the lower house to stay in power, although its ability to push through planned reforms would be hampered.
The cabinet has already been weakened by several graft scandals, including allegations that Defence Minister Alexandr Vondra, a key ally of Necas, had overseen an overpriced services contract during the country's EU presidency in 2009.
Vondra denied any wrongdoing but coalition partners have been calling for his departure. (Reporting by Jan Lopatka and Robert Mueller; Editing by Andrew Heavens)