Congress, which has sought her resignation, asked the Centre to make public all letters it had written to the UK government on Lalit Modi and insisted that Swaraj's help to him for getting travel documents was a clear case of quid-pro-quo.
"In the interest of transparency, Government of India should release the letters written to the UK Chancellor on the Lalit Modi case", Congress leader P Chidambaram said.
The former finance minister had vigorously pursued with the UK government the issue of his deportation to India.
Congress spokesperson P L Punia said Swaraj and Lalit Modi were in contact for long. "As a quid pro quo, Swaraj has done favour to a tainted person who is accused of Rs 700 crore money laundering...," he said terming as "complete bogus" her defence that she helped him on humanitarian ground.
Bihar Chief Minister Nitish Kumar latched on the controversy to target the Modi government over its probity claims and said the entire government was in the "dock" following the incident.
"What is clear from the support (to Swaraj) extended by the government, party (BJP) and RSS that they will help their own even if a crime has been committed. The whole government is in the dock. The way it had defended (her) means there is no reason to believe that it was not aware of the matter," he told reporters in Bihar.
Swaraj, however, found strong support from NDA ally Shiv Sena with its spokesperson Sanjay Raut saying she was being targeted to "weaken and destabilise" the Modi government.
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"The way the External Affairs Ministry had performed under Swaraj, it has become a strong pillar of the Modi government. She is being targeted to weaken the government and destabilise it," Raut said, adding Prime Minister Narendra Modi should see through it.
Union minister Rajiv Pratap Rudy said the way she had been attacked was "completely unacceptable", claiming that the whole nation knew about her political background and work.
Bahujan Samaj Party chief Mayawati said in Lucknow that she was not surprised with the row.
"After the failure on the front of peoples welfare in its first year in the office, it would not be surprising if cases of moral and other corruption came to the light in the second year of Modi government," the former UP chief minister said.
Congress leader and Swaraj's predecessor Salman Khurshid said that BJP was making its case "worse" by hiding facts and asked the Centre to come out with truth.
Noting that the UPA government had pushed for Lalit Modi's extradition from the UK, he sought to know if the Modi government had "reversed" Indian stand and charged it and BJP with practising "double-speak".
CPI (M) General Secretary Sitaram Yechury demanded that the prime minister tell the nation how the matter is going to be addressed, terming the charge against Swaraj very serious.
"First of all, there are very serious charges raised against the external affairs minister. But the prime minister has been quiet and silent.
"We are asking the prime minister to tell us how this is going to be addressed... So, in this situation, the prime minister, whose prerogative it is to keep whomever he wishes in the Council (of Ministers), has to answer this," Yechury told reporters.
Trinamool Congress leader Saugata Roy said Swaraj should not have had intervened in the matter and now she must own up to having done something "improper" in her capacity as a minister.
Aam Aadmi Party dragged the Prime Minister's Office into the row, alleging "PMO may have been in the loop". Party leader Kumar Vishwas also played on the BJP's "internal power tussle", suggesting that the prime minister might have wanted to cut her to size.
Anti-corruption activist and Supreme Court lawyer Prashant Bhushan said there was a need for a conflict of interests law in the country and pressed for her resignation.
Nitish Kumar said the whole affair has brought to fore the internal differences in the government as finance ministry under Arun Jaitley was probing cases against Lalit Modi while the foreign minister was helping him.
Congress workers also protested outside Swaraj's residence, demanding her resignation.
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