The Wisconsin governor's executive order comes ahead of his departure for Israel on Friday with a 15-member trade group, running until November 2.
"We stand firmly against discrimination in any form and we wholly support our friends in Israel," said Walker, adding: "I look forward to leading a trade delegation to Israel to foster new trade partnerships between Wisconsin and Israeli businesses."
Wisconsin becomes the 24th US state to pass either an executive order or state law outlawing BDS activity targeting Israel.
The executive order states: "Consistent with existing Wisconsin nondiscrimination provisions of and regulations governing purchases… agencies may not execute a contract with a business entity if that entity is engaging in a boycott of Israel. Further, agencies shall reserve the right to terminate any contract with a business entity that engages in a boycott of Israel during the term of the contract."
The order says "boycotts based on religion, national origin, ethnicity, or residence are discriminatory" and:
the Boycott, Divestment and Sanctions (BDS) movement against Israel serves to inflame conflict; and over 20 states have enacted laws or resolutions against the BDS campaign.
According to Walker's statement, Israel-Wisconsin trade relations are flourishing, with "with Wisconsin exporting over $80 million annually to Israel and importing over $200 million annually from Israel."
Walker is a Republican who was a presidential candidate in 2016.
The proposed bill "would prohibit any entity in state government or local government from adopting a rule, ordinance, policy, or procedure that involves the entity in a boycott of Israel, or a boycott of a person doing business in Israel or in a territory under Israeli jurisdiction. The bill also requires that state contracts for materials, supplies, equipment, and services include a provision that the vendor is not currently participating in and will not participate in a boycott of Israel during the contract."
The Israel Project's CEO and President Josh Block said, "The Israel Project is grateful to Governor Walker for his leadership in fighting against BDS discrimination. For years, Israel – and only Israel – has been targeted by this deceptive attempt to delegitimise its very right to exist. BDS proponents do not seek a better life for the Palestinians, nor do they aim to create a political environment favorable to a lasting peace between Israel and its neighbors. Their true aim is the destruction of the Jewish state."
Block added, "From the North to South, in blue and red states – and with strong bipartisan support – lawmakers in 24 states have now declared BDS a form of discrimination and sent a clear signal that their states will not tolerate or condone taxpayer dollars going to subsidise anti-Israel hate."