The arrest of A Raja , which had become inevitable after the deadline set by the Supreme Court for CBI to submit its progress report on the probe into the 2G spectrum scam , is expected to be used by the Congress-led UPA government to stem its slide in the popularity sweepstakes, besides attempting to take the sting out of the Opposition's campaign for a JPC probe.

The move, which comes ahead of the budget session of parliament, which commences on February 21, is being seen as a UPA's political damage-control exercise. The government obviously does not want the budget session to go the same way as the previous session was over the demand for a JPC probe.

The arrest of the DMK leader is certain to be used by Finance Minister Pranab Mukherjee to convince opposition leaders about the government's sincerity in exposing the string of scams that have scarred its image.

"Some of the underlying reasons for the demand for a JPC probe have gone now. The deadlock should also end with this," a senior Congress leader said.

Wary of the credibility-deficit that had come to haunt the government in the wake of scams, government managers are hoping to use its interventions in the Adarsh Housing Society and the Commonwealth Games scams to publicise its intention of undertaking some urgent measures to book the guilty.

Notwithstanding Raja's arrest, the move is expected to raise more difficult questions for the Congress in the coming days. Prime Minister Manmohan Singh had put up a concerted defence of Raja in Parliament for a long time and new Telecom Minister Kapil Sibal had said the CAG report on presumptive loss of Rs 1.76 lakh crore in 2G spectrum allocation was erroneous.

Congress sought to take the high moral ground over the arrest and said that the government and the prime minister's conduct are above board. It brushed aside suggestions that it was the Opposition pressure that led to Raja's arrest.

"All the doubting Thomases who doubted the sincerity of commitment to take action as per law should have been silenced. Law has taken its own course in the case.

We are not concerned about the innocence or guilt of the accused. All those who raised questions, should be silent by now. The credibility of the government stands enhanced,'' party spokesman Abhishek Manu Singhvi said on Wednesday.

Raja's arrest, however, will not affect Congress-DMK ties in Tamil Nadu and neighbouring Puducherry, even though Congress is expected to nudge its partner to part with more seats in the ensuing round of assembly polls.