KIEV, Dec. 9 - Ukraine and Russia, deadlocked for nine months in a natural gas dispute, were drifting towards a political clash after officials suggested the dispute may affect stationing of Russian troops in Ukraine.

Anatoliy Matviyenko, the deputy chief of staff at President Viktor Yushchenko's office, said Ukraine may seek to increase rent payments that it charges Russia for stationing its Black Sea Naval Fleet in Sevastpol.