Rebellion in Trinamool Congress is set to boost NDA numbers in Parliament as it strives for a two-thirds majority in both Houses to help pass crucial Constitutional Amendment Bills. 

While the current round of Rajya Sabha elections will help the NDA inch toward the two-thirds mark, in the Lok Sabha, it is still far from that magic figure of 263, despite the TMC switchover. 

Sources said that from its current strength of 148 MPs, the NDA is set to gain three seats in the current round of RS elections by winning the independent seats in Jharkhand and Mizoram, where elections are being held. 

With three TMC MPs resigning, the NDA is set to secure all three seats from West Bengal after the bypolls, upping its tally to 154, nine short of a two-thirds majority in the Upper House. 

As more TMC MPs are likely to resign in the Upper House, the NDA may achieve the figure of 163, which will give it the numerical strength to pass all constitutional amendment bills. 

The ruling alliance's strength may decrease by November when 10 MPs from Uttar Pradesh retire, and the Samajwadi Party may gain some seats in the Rajya Sabha, with its improved numerical strength in the State Assembly. 

The Opposition INDIA bloc currently has 64 MPs on its side, after the exit of DMK with eight MPs and AAP with three MPs distancing itself from the grouping. 

Independent parties such as YSRCP and BJD, with seven and six seats, and MDMK, can go either way in the Rajya Sabha. 

In the Lok Sabha, however, the NDA's numbers can go up to 213 with around 20 more TMC MPs forming a separate group and supporting it. 

The defected MPs are set to meet Speaker Om Birla on Monday and hand over a letter announcing their separation from the TMC.  In the Lok Sabha, 363 MPs are needed to get a two-thirds majority.