A current 'inauspicious' phase in Hindu calendar is believed to be holding back the Bharatiya Janata Party-led opposition from naming its presidential candidate.

A senior BJP leader said a consensus had almost been evolved within the NDA over declaring vice-president Bhairon Singh Shekhawat as the opposition's candidate for the election to the highest office.

"But it is Mal Mas in Hindu calendar these days. It's not considered auspicious to make key announcements during this period," the BJP leader said.

The Mal Mas will last until middle of the next month, while President A P J Abdul Kalam's term expires in July.      

The NDA has authorised its chairman Atal Bihari Vajpayee to name the opposition's presidential nominee and NDA sources say the BJP-led alliance has been lobbying different political and non-political groupings to win support for Shekhawat.

"We do hope that in the event of an election, there could also be cross-voting which may lead to the success of our candidate," a BJP source said.

Earlier this month, Trinamool leader Mamata Banerjee suggested Vajpayee be declared the NDA's presidential nominee, a proposal the 84-year-old leader declined.