NEW DELHI (AFP) - India's Hindu nationalist opposition said on Tuesday party patriarch Lal Krishna Advani would return to the fold, a day after he quit in apparent protest at the naming of hardliner Narendra Modi to head the 2014 election campaign.

In a shock move, Mr Advani, an 85-year-old stalwart of the Bharatiya Janata Party (BJP) and a former deputy prime minister, resigned on Monday from all his positions in the party which he helped build into a national force.

Mr Advani's resignation was rejected by the BJP's parliamentary board amid high drama that followed his decision.

On Tuesday, BJP president Rajnath Singh announced that Mr Advani would continue to "guide the party in the national interest".

Mr Singh said he had assured Mr Advani that his concerns about the functioning of the party would be "properly addressed".

Mr Advani "has said that any decision of the party he will accept," Mr Singh said.

Mr Modi's appointment as campaign manager at a weekend party meeting in the coastal state of Goa is seen as a stepping stone to him being named the BJP's prime ministerial candidate.

Mr Modi's elevation came despite resistance from some colleagues who view the chief minister of Gujarat as an electorally divisive figure for failing to stop deadly anti-Muslim riots in 2002 in his home state.

BJP leaders gathered at Advani's residence to make the announcement that the veteran leader was staying on in the party.

However, Mr Advani was not present at the news conference for what Mr Singh explained were "reasons of common etiquette". He did not elaborate.

In a terse resignation letter, Mr Advani had said he was "finding it difficult to reconcile with either the functioning of the party or the direction in which it is going".

"Most BJP leaders are concerned just with their personal agendas," he wrote in an oblique reference to controversial right-wing leader Mr Modi.

Mr Advani, who built the BJP into the only national opposition to Congress, had snubbed the party conference where Mr Modi was named campaign chairman.

Mr Advani's unhappiness highlighted the difficult road ahead for Modi who will need to win the backing of other senior BJP members as well as the party's regional coalition partners to become the party's candidate for prime minister, analysts say.

Analysts also say the dissent could hurt the BJP's chances of recapturing power despite widespread public anger against the ruling Congress over corruption scandals.

The general elections are slated to be held by May of next year.