"In politics, there are no permanent enemies or permanent friends. We will decide as the situation evolves," he told reporters at Rashtrapati Bhavan.
He was replying to a question whether Congress looks at JD(U) as a future ally against the backdrop of the split in the NDA and would reach out to it.
To a question on Nitish Kumar, he said the JD(U) leader is secular.
Singh refused to comment on the elevation of Gujarat Chief Minister Narendra Modi in the BJP and the resignation issue of L K Advani.
"This is an internal matter of the BJP," he said.
On the Federal Front mooted by West Bengal Chief Minister Mamata Banerjee, he said "I cant see the Federal Front posing a real challenge to the UPA."
"When the chips are down, the UPA will give a good account," Singh said.
