The Indian government will impose presidential rule in the southern IT hub state of Karnataka after the chief minister resigned as his coalition ally refused to back him in a confidence vote.

The Bharatiya Janata Party's B S Yeddyurappa quit after a week in power when the Janata Dal (S), junior partner in the coalition government, set conditions for its support, such as ministerial portfolio demands, which were rejected by the BJP.

'The cabinet has recommended presidential rule in the state,' said a government official.

The local political crisis is a blow for the BJP as the party, with a small presence in other southern states, hoped to use Karnataka as a gateway to the south and gain a larger national footprint to eat into support of the ruling Congress party.

Karnataka's capital Bangalore is India's IT capital, and political instability in the state over the last three years has also hampered governance while the city's infrastructure woes have only worsened, residents say.

The Janata Dal (S) wanted the BJP to sign a pact agreeing to its demands before a confidence vote, but the latter had said it would consider doing so only after.

The BJP chief minister quit without seeking a vote after the Janata Dal (S) ordered its legislators to vote against the confidence motion.

With elections seen as the most likely way out of the political turmoil in the state, BJP expects that the Janata Dal (S) decision to renege on its word would generate sympathy votes for the Hindu nationalists, some analysts said.

The BJP was supposed to come to power in Karnataka last month under an agreement with the Janata Dal (S) to rule the state for 20 months each.

But it ended up pulling out of the coalition after the Janata Dal (S) reneged on the pact and refused to hand over power, forcing New Delhi to impose federal rule last month before the two sides briefly patched up their differences. Reuters