Mishra's reaction came a day after Dhankar attacked Chief Minister Arvind Kejriwal for opposing SYL canal construction, saying Haryana will not be able to deliver water to Delhi and asked him to get "your own canal constructed" for carrying Delhi's share of water.
The Delhi Minister said Dhankar does not have "understanding of laws".
"Haryana minister perhaps has not read the Constitution. Secondly, he does not have the understanding of laws and third, he is not aware about the dignity of his post.
In a letter to Kejriwal, Dhankar had said that seeing his stand (opposing the construction of SYL canal in Punjab) Haryana will not be able to deliver the share of water in Delhi since he had stood against the interests of the farmers and people of Haryana.
Terming Kejriwal's stand as "wrong", Dhankar said he had opposed the proposed canal for "political benefits" in Punjab.