United Progressive Alliance chairperson Sonia Gandhi and Defence Minister Pranab Mukherjee started their one-day visit to the flood-affected regions of Gujarat on Thursday morning.
Sonia and Mukherjee began their aerial survey from Vadodara to Surat, soon after they reached Vadodara at around 8 am.
They were received by Union Textiles Minister Shanker Singh Vaghela and other state Congress leaders.
The Congress president and Union Home Minister Shivraj Patil on Wednesday conducted an aerial survey of the worst-affected districts of Andhra Pradesh.
The flood situation in Surat worsened on Wednesday with the water released from Ukai dam on river Tapti paralysing road and rail traffic.
The whole of Surat is now under water, Flood Control sources said.
More than 2,00,000 people have been evacuated from flood-affected regions of the state.
In Surat, the telecommunication network, including mobile and landline services, was disrupted by the floods and the administration used satellite phones and ham radios to tide over the problem to some extent, officials said.
Gujarat Chief Minister Narendra Modi, who made an aerial survey of the flood-hit areas on Wednesday, appealed to the Centre to release an immediate interim assistance of Rs 2,000 crore to tide over the crisis.